Marco-035

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SPARTAN-035, also known as Marco-035 and Marco Wade, was a SPARTAN-II commando of the secretive Project SIGMA. Marco was a versatile Spartan and was proficient in most fields of combat, though he was best known for his skill in close-quarters fighting. Marco served with distinction during the and participated in numerous battles alongside his team.
Marco was one of the preliminary 150 candidates selected by Dr. as part of the SPARTAN-II Program. Due to budget restraints, he became one of the seventy five not abducted and would have lived a normal life, were it not for the creation of secretive offshoot of the program known as SIGMA. Marco and nineteen others were abducted and given identical training to that of Halsey's Spartans on Reach under the tutelage of Richard Mack Senior.
In 2525, Marco underwent the surgical augmentations that would transform him into a Spartan. He and the others survived the augmentations and were split into separate teams, each under the impression that their own group were the only living members of SIGMA. Shortly after, Jack-085 and Ahmad-126 tried to convince him to leave the base and go on the run. Marco reluctantly declined, leaving the other two Spartans to escape. He would then join Sigma as they embarked on a series of operations against the Insurrection.
After the Human-Covenant War broke out, Marco fought valiantly in hundreds of battles and campaigns, participating in major events such as the Siege of Fargad, and the . Following the conflict's end, he and his fellow SPARTAN-II's remained as part of the UNSC Navy instead of joining the newly-formed and continued to participate in classified operations on ONI's orders. Known for his stubborn nature and somewhat flippant attitude by Spartan standards, he remained as an efficient, dependable soldier who never backed down when a battle could be won.
==Career Service Vitae==
{| class="property" style="padding:0px; border-radius: 0 0.5em 0 0.5em;"		
;Marco 
;Chief Petty Officer
FULL NAME: Marco John Wade
SERVICE #: 035
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Unit: SIGMA-Alpha
NEC: UNKNOWN
Enlistment Date: CLASSIFIED
Location: CLASSIFIED
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Gender: M
Birthplace: Earth
Birth Date: 02/04/2511
Blood Type: O
Height: 210 centimetres (6.9 ft)
Weight: 130 kilograms
;Report Date: December 9th, 2557
;Performance
S-035 has an impressive enemy KIA record that numbers in the thousands after over thirty years of service. His aggression on the battlefield has been noted by observers with reports indicating that due to his excessive violence any mission footage against human combatants should not be shown in mainstream media reports. Even for a Spartan, S-035 has proven himself to be incredibly adaptable and performs to a high standard both when alone and as part of a larger team. 
However, he has shown a great attachment to his squadmates and has risked his own life to save his fellow Spartans on numerous occasions. In the aftermath of a friend's death he has exhibited an extreme amount of anger and a desire to take revenge that surpasses given orders; the sudden demise of SPARTAN-041 during a friendly fire incident during the and the sudden pursuit of Codename: PYRRHUS - a high ranking civilian consultant for ONI and director of Project SIGMA - may have ended in S-035 murdering the scientist, though the event was never thoroughly investigated due to the urgency of the war. 
As a SPARTAN-II, he has seen decades of warfare and is seen by others as a walking legend due to his years of experience. While he keeps his interactions with non-Spartan personnel to a minimum, S-035 has exhibited surprising camaraderie with fellow UNSC troops and is a definite boon in the field for any allies. Like most of the surviving SPARTAN-II's, S-035 has extensive experience in combating Insurrectionist rebels in addition to Covenant forces and though he has noted his preference for fighting aliens, seems to be performing well without noticeable signs of severe stress or fatigue. Nonetheless, S-035 should be given mandatory psych tests once every six months to check for any signs of wear and tear; given his suppressed emotional issues and the circumstances surrounding PYRRHUS during the war, it is recommended that he should be kept under long-range observation while not in the field.
	
==Biography==
===Early Life===
Marco John Wade was born in the 's capital city of LondonAlso the author's birthplace. This is the only similarity between the author and Marco. on on April 2nd, 2511 to two immigrants from from . From an early age Marco exhibited many superior qualities that marked him from his peers, including heightened intelligence, strength, and stamina. Growing up in London was tough for the young Marco as his parents struggled to make ends meet for several years, relying on various daycare centres to look after the child. Despite these hardships, he had a fairly happy, normal childhood. When Marco was three years old, his younger brother, Michael, was born. Even at this early age Marco felt a natural instinct to protect his younger sibling and often looked out for him over the next few years. 
During his first year of schooling at age five, Marco was first noticed by the Office of Naval Intelligence after a routine blood test and report, which noted his advanced mental and physical capabilities. These qualities marked him out as a viable candidate for the SPARTAN-II Program. In early 2517, two agents from the organisation visited Marco's school under the guise of parents looking to move their child there. One of the agents briefly interviewed him, asking various questions pertaining to his views and personality. In spite of his young age Marco was able to answer everything, though he saw through the kind facade the agent was putting on and left after becoming uncomfortable with their presence.
After some time, Marco was placed in the list of seventy five candidates who would not be used for SPARTAN-II due to funding reasons and his location on Earth; ONI found it easier to kidnap children from the Inner Colonies. Dozens of others were taken to Reach for training, leaving Marco as one of the lucky few who were left alone. This would not last, as Calvin Roe, a scientist working in the same intelligence division as , was informed about SPARTAN-II and managed to convince the upper echelons of ONI to create a second group of Spartans on Earth after citing concerns over Halsey's methodologies. This was accepted, and Marco and nineteen others were selected for abduction while facilities were made for this group's training. 
===Training===
Marco was abducted at the age of six by agents while playing outside his house and taken to a secret military base in the United Republic of North America, where they were briefed by Doctor Roe. Marco hated the scientist's callous attitude and cold demeanour towards him and the other children from the moment they met, and was punished for shouting at the Roe his first day. Shortly afterwards, Marco would meet Lieutenant Colonel Richard Mack Senior, a renowned member of the UNSC's special forces who oversaw their gruelling military training. While harsh towards the trainees, Mack also gave encouraged them to succeed at any cost and soon gained Marco's respect. The young boy soon became fascinated with Mack's war stories and dreamed of becoming a hero. Marco adapted fairly quickly to his new life because of this, though he refused to forget about his brother and parents even as he was indoctrinated to see his fellow trainees as a surrogate family.
The young Spartans were also educated by Leonard, a 'dumb' AI that taught them a great deal about military history and strategies alongside many basic skills such as writing and mathematics. While never top of the class academically, Marco developed an interest in ancient history during this period and spent a great deal of his free time during training reading books on old civilisations. He would also become good friends with Wulf-041, Jack-085, Elena-071 and Nef-015 early on, though he preferred to partner up with Elena during sparring sessions as the two got along well with almost no disagreements. Jack would occasionally show jealousy towards their close friendship, though Marco always tried to make him feel like part of their group.
He and Elena often came out near the top when working in a pair, and with Jack they were nigh-unstoppable in most training situations. In spite of this, they could never best the likes of Fenn-145 in combat simulations, something that infuriated Jack but did not particularly bother Marco or Elena. Nonetheless, the trio's determination impressed the likes of Mack, who often commended them for trying their hardest to succeed no matter what. Doctor Roe, on the other hand, would often try to split them as he believed that Marco relied too much on his better-performing comrades to make up for his shortcomings. The implementation of a leaderboard for the SIGMA Spartans by Roe only made the trainees strive harder to win, though it began to drive a wedge between Marco and the ultra-competitive Jack in the last year of their training.
At the age of fourteen, Marco and the other candidates were taken for the augmentations that would make them into the supersoldiers the UNSC needed. Nine of them, including Elena, were apparently killed during the augmentations. Unbeknown to Marco's team, there had not been any casualties and the Spartans had simply been moved into separate groups, each with a specific purpose assigned to them by the Office of Naval Intelligence. Distraught over losing Elena, Marco spent several days in mourning before pulling himself together at Mack's request and focusing on his recovery. 
Three weeks after their augmentation procedures two of the Spartans, Ahmad-126 and Jack-085, chose to put their improved bodies to use by breaking out of the SIGMA facility in a bid for freedom over seven years in the making. The two were confronted by Marco during their escape, though despite Jack's pleas he refused to leave with them and genuinely believed that they could make a difference for mankind as Spartans. Jack angrily insulted Marco, calling him a coward for accepting a 'slave's life' before leaving alongside Ahmad. Confused and upset by his friend's betrayal, Marco did not pursue them and allowed the pair to escape unhindered.
Marco's failure to stop Jack and Ahmad would soon prove to be one of his greatest regrets, as shortly after their escape Ahmad was found dead, having apparently been murdered by Jack after a disagreement between the two. In spite of a massive search by ONI, the rogue Spartan was never caught and Marco was harshly rebuked by both Calvin Roe and Richard Mack for letting them leave. While he was not punished, it was made clear that they were greatly disappointed in him and that any prospects of a leadership position in the future were now gone. While he expected to become a pariah among his fellow Spartans because of this, the rest of SIGMA would stand by Marco and lifted his spirits, making it clear that in spite of his mistakes they were still family. Though he felt more alone than he ever had without Elena and Jack around, Marco resolved to face whatever the future would throw at him.
===First Mission===
In January of 2526, Sigma Team was sent on their first mission against a large Insurrectionist force that had entrenched itself on the small colony world of Gallis. While UNSC forces had been able to defeat them in open combat and had driven most underground many survivors had taken a sector of the capital city and were threatening a mass killing with a captured FENRIS nuclear warhead unless their demands for a copious amount of supplies were met. Eager to test the unblooded Spartan group, ONI dispatched Sigma Team to eliminate the threat as quickly and efficiently as possible. Armed for the first time with suits of MJOLNIR Mark IV armour, Marco and the other Spartans were nigh-unstoppable as they split into three teams of three and infiltrated the capital through its sewer systems and easily wiped out a number of patrols. Working alongside Kane-098 and Jacob-076, Marco's task was to find and capture the rebel leader, who had been sending out encoded transmissions to his forces from within their main camp. 
Moving through recently-abandoned city blocks, Marco killed for the first time as he eliminated an enemy patrol, slitting a man's throat with his combat knife before breaking the neck of another with his armoured hands. Acting on his years of training, the Spartan felt nothing for the rebels as he and his comrades proceeded into their camp. While a transmission from Fenn-145 revealed that the threat of a nuclear weapon had been a lie, there were a number of civilians still being kept prisoner by the armed rebels. Linking up with some of the other Spartans, they soon freed dozens of innocent people and continued to effortlessly wipe out all resistance, though the alarm had been raised and the remaining rebels were attempting to converge on their location for a counter-attack. 
Unwilling to be put on the defensive against numerous platoons of incoming Insurrectionists, Marco and the others chose to attack, launching an assault that surprised the rather poorly-equipped rebels within their camp, building up a momentum that smashed any advantage their foe possessed. While he had been trained for years utterly dehumanise the enemy and kill without hesitation, Marco felt somewhat ashamed for participating in what was essentially a massacre against dozens of rebels as most died either without weapons or while trying to retreat or surrender to the Spartans. While Sigma Team mopped up the survivors, Marco entered the enemy leader's room, only to find it empty and full of communications equipment. After realising that the rebel commander had likely not been on Gallis for some time, the Spartan was confronted with a recorded message that mocked the Spartans specifically. Fully aware of the secrecy of his program, this surprised Marco, who quickly fled the room as a timer began to count down.
As Marco exited the building, numerous explosive devices detonated inside that sent the Spartan flying but left him otherwise unhurt. Kane and Jacob approached him, asking what had happened. He told them that the rebel leader had already left the planet, and that the building was trapped with explosives. Soon, the other Spartans radioed in to request assistance against a small redoubt of surviving rebels. Marco and the others hurried back to their location and swiftly overwhelmed their foes in. Fenn-145 then called in the waiting UNSC forces, who secured the area and liberated the capital from insurrectionist control. Sigma Team was extracted by Pelican, delivering them to a nearby Prowler that would return them to Earth. Marco was silent the whole way back, pondering over the message, and how this rebel leader had somehow known that they would come. While he feared that Jack-085 had been leading the rebels on Gallis, he could not back up this belief and told no one of the recording.
When they returned to the SIGMA facility, they were greeted by Doctor Calvin Roe and Lieutenant Colonel Richard Mack Senior; the latter had returned briefly from Reach for their 'graduation'. Like the other Spartans, they were assigned to the UNSC Special Warfare Command. However, Sigma Team answered to orders directly from ONI above those of the Navy. They were also given their official military ranks. Marco was unsurprised to see Fenn-145 made team leader as a Master Chief Petty Officer, while Kane-098 placed as second in command. While the rest of Sigma were granted the rank of , Marco's inaction against Jack and Ahmad's breakout and years of animosity between him and Roe came back to bite him as he was informed of his own rank: . This put him as the lowest-ranking SPARTAN in Sigma Team, though it had little function other than to humiliate him.
Such a petty action only solidified Marco's hatred for Roe - who had certainly pulled strings to abuse Marco - before they left the SIGMA complex on Earth for good. Sigma Team would spend several years destroying Insurrectionist groups in the Inner Colonies as news of the Covenant threat began to spread and entire worlds were destroyed by the relentless alien forces.
===Contact with the Covenant===
Main Article: Skirmish on Brennus
On the 21st of December, 2530, Sigma came into contact with Covenant forces on land for the first time after several years of destroying Insurrectionist strongholds. The Spartans were sent to a research station on the outer colony world of Brennus. The station had gone quiet, and not knowing if it was Insurrectionists or Covenant, The nine Spartans were given orders to secure the station, and destroy any kind of navigational data, as per the Cole Protocol. When the Spartans moved towards the facility, they found it overrun by Covenant forces. Fenn-145 ordered Marco, Nef and Wulf to flank the large number of enemies outside and move into the building while the other members of the team got the attention of the enemies guarding the facility, and would secure the perimeter, ensuring that no Covenant soldiers could escape if they had any data.
Marco's team moved into the facility, eliminating several hostiles as they cleared it out. Eventually, they came to the main data centre, where they found an species of alien that appeared to be accessing the Facility's database. Nef-015 shot it in the head, killing it instantly. Having secured the perimeter, Sigma Team then set explosive charges around the base after purging the computer systems. They destroyed the facility to make sure that the Covenant could not make use of it in any way. Sigma Team was then extracted from the colony via Pelican after destroying the research facility, having ensured that no data was captured by the enemy. Brennus was glassed several months later when Covenant ships arrived to find their advance teams wiped out. The experience of battling the Covenant on the ground proved to ONI the effectiveness of their SPARTAN teams against the enemy.
===Battle of Sethlans=== 
In June of 2534, several members of Sigma Team were dispatched to the Outer Colony world of Sethlans after news spread of Covenant sightings on the planet. While the colony had few settlements outside of large-scale mining stations due to its inhospitable terrain, it was important enough to warrant a Spartan deployment, with an Orbital Drop Shock Trooper team known as Whiskey-04 to act as backup for the supersoldiers. Alongside Jacob-076, Nef-015 and Wulf-041, Marco arrived quietly in a retrofitted U81 Condor, provided by the Office of Naval Intelligence. With the SPARTAN-II Program and Sigma in particular still an official secret, they allowed Whiskey-04 to handle the colonists after their own landing in a small Corvette while they spread out to begin their investigation.
After spending almost a day trudging through the volcanic landscape of Sethlans, the Spartans sighted a Covenant Ghost moving across the landscape ahead of them, followed closely by a heavy-duty miner's vehicle. Though on foot, they were able to track the pair to a cave network miles away from the primary settlement, guarded by a number of Jackals. Spending several hours monitoring the base, they correctly surmised that the colonists were trading equipment with the Jackals - known for their rather unscrupulous behaviour - in secret, possibly in exchange for their colony's continued survival. As the Human vehicle departed the caves, Jacob ordered Nef to take the driver into custody while the others eliminated the alien threat. Marco and Wulf led the attack, moving inside while Jacob covered the entrance from afar. While heavily outnumbered, the two Spartans took their foes completely by surprise and killed dozens as they moved inside the cave. Most who attempted to flee were taken out by Sigma's marksman as they exited onto open ground, though several Jackals managed to evade them and made it aboard a shuttlecraft, taking off from Sethlans before the Spartans could stop them.
Fearing immediate reprisal from a larger Covenant military force, Sigma contacted Whiskey and requested that they have the colonists prepare for a possible attack. They then met up with Nef, who had ambushed the mining vehicle and arrested both men inside. It took little questioning for them to reveal that they had been trading a cut of the minerals they mined to the Jackals in exchange for Covenant fusion reactors, whose power output far surpassed those of any Human machines. While the civilians argued that the Jackals they had traded with possessed no ill-will towards Humanity and were supposedly unaffiliated with the Covenant, Marco harshly rebuked them for putting their entire planet in danger before heading back towards the local settlement. It was there that they met up with Major John Ackton and the rest of Whiskey, who had discovered the Covenant reactors. As it seemed like only a tiny fraction of the colonists were aware of their existence and there was a very real possibility of Covenant invasion, the Spartans neglected to investigate further and focused on preparing the colony for attack.
As Sethlans was primarily a mining colony, there were few weapons aside from some small arms carried by security guards, though some mining equipment could be repurposed for battle if need be. While there was no activity overnight, word arrived the following morning that a Covenant had arrived in-system and was heading towards the planet. While an emergency hail had been sent out, UNSC forces were at least a day away via slipspace travel and the corvette the ODST's had arrived in would stand no chance against it in combat. To make matters worse, Sethlans' possessed too few transport ships to evacuate the entire population, as it largely relied on the monthly shipping vessels that transported ore to take people in or out-system. Unwilling to abandon the populace to their fate, Sigma quickly formulated a dangerous plan to launch a counter-attack. While they had cleared out the caves, the Jackals had left a great deal of valuable equipment behind. Knowing that the aliens were greedier and more materialistic than their faith-driven brethren, Jacob had Marco and Wulf return there and wait for them to come back for their possessions while he and Nef protected the mining settlement alongside Whiskey-04.
Before long, Phantom dropships began arriving from orbit to attack the colony, unleashing hordes of vicious Covenant warriors. Still waiting in the cave, Marco was told by Jacob that the attack force seemed to primarily be made of Grunts and Jackals, with no sightings of any feared Elite warriors or monstrous Hunters that usually made up the backbone of alien forces. Nearly half an hour into the battle, the same shuttle arrived at the cave, filled with Jackal raiders. The birdlike aliens were so intent on retrieving their treasures that they did not notice the Spartans until it was too late. Killing the group in seconds, the pair managed to hijack the shuttle before they called for help and left Sethlans' atmosphere without any trouble, heading back towards the destroyer. As they neared it, Marco noticed that it seemed heavily damaged, while Wulf noted how unusual it was for the Covenant to send a single ship to a planet when any Human activity was usually meant with a fleet capable of glassing an entire world. Surprisingly, Wulf's mediocre piloting skills went unnoticed as they landed in the ship's hangar and surprised the deck crew, sweeping through the destroyer's corridors as quickly as possible. When they reached the bridge, the Spartans were surprised to find the vessel captained by a Jackal Shipmistress, whose paltry defence was no match for the two supersoldiers. Furthermore, the ship was in terrible shape; most of its weapon systems were offline and the hull bore the marks of numerous plasma strikes. Correctly assuming that this was a pirate vessel instead of a Covenant military ship, Marco suggested that they simply sabotage the ship's engines and leave before it blew, retrieving any valuable data for ONI to analyse later. 
With most of the destroyer's crew fighting on the ground, the Spartans met little resistance en-route to the engine room, where they planted several plasma charges stolen from the ship's armoury. Marco and Wulf quickly escaped in the shuttle they'd arrived in, making it back to Sethlans' surface as the vessel blew apart in orbit. The battle, though vicious, had been won with no casualties; Whiskey and Sigma's superior tactics had easily undone and torn apart the assault force. With Sethlans more or less safe, the Spartans had most of the populace kept in their homes for the next day while they supposedly scoured the surrounding area for hostiles. In reality, Major Ackton had ordered for those collaborating with the Covenant to be interrogated and the Covenant fusion reactors removed, just in case. Backup arrived the following morning in the shape of a sizeable Battlegroup, whose Marine contingent took over on the ground while the SPARTAN-II's and Whiskey-04 quietly left the system. Though they had saved the planet, their actions would likely never see the light of day due to the heavy veil of secrecy surrounding Project SIGMA and SPARTAN-II as the victory was attributed to the vague 'UNSC Special Forces' in the media afterwards. 
===Battle of the Bonanza Asteroid Belt===
In early 2537, Sigma Team were alerted to an impending Covenant attack on a UNSC fleet in the far-off Bonanza Asteroid Belt. While nowhere near the war's frontlines and on the very edge of colonised space, the Office of Naval Intelligence had a science station located on one of the larger asteroids and the area had been used as a staging ground for UNSC ships to repair and refit en-route to battle using hidden SSR stations. After Covenant forces had managed to fit a tracking device on a Frigate fleeing a far-off skirmish, they were able to move in a fleet to the system. With enemy ships moving over the belt and dispatching thousands of troops to search for UNSC outposts, ONI brought in the Spartans to secure any research data and fend off the Covenant by any means necessary. 
Deploying in the asteroid belt from an ONI Prowler, Marco was part of a team with Fenn-145, Jax-007 and Nef-015. While the rest of Sigma moved to lay mines across the outer edges of the belt to trap the incoming Covenant forces, their group was to move in and secure the research data. Having heavily modified their MJOLNIR suits to help them move and fight for longer in a vacuum, Marco's team soon arrived at the station to find it already under attack by a group of Sangheili Rangers. Though the Spartans easily dispatched them, their foe was able to signal for reinforcements, forcing the Spartans inside as Covenant dropships broke through the heavily-trapped asteroid field towards their position. After ordering Nef to secure all data held within the facility, Fenn had Marco and Jax escort the remaining scientists and guards to the nearby shuttle bay as they began an evacuation. 
As Marco and his comrades prepared the shuttles for launch, they were informed of a newly-arrived UNSC battlegroup, called in to repel the Covenant attack. Due to the asteroid belt's close proximity to many valuable refit stations and the dangers of using MAC guns in such an environment, the allied ships used the rocks for cover to move in close to their foes before deploying hundreds of EVA-equipped . While an incredibly risky and near-suicidal move in tactical terms, these troops were able to board the Covenant vessels and within the hour had blown apart three from the inside. Watching from afar as they fended off waves of attackers by the facility, Marco was impressed at the mission's success, though he was unaware of the existence of SPARTAN-III's at the time. Eventually the last-remaining Covenant vessel, a damaged CCS-class Battlecruiser, attempted to retreat from the system. As it moved out of the Bonanza belt to attempt a slipspace jump, it triggered a number of HORNET mines placed by Sigma's insertion Prowler that badly damaged its shields and hull and allowed the nearby UNSC Frigates to destroy it with volley after volley of missiles.
Sigma Team were retrieved from the asteroid belt shortly after regrouping at the science station and covertly left the system that day. While the UNSC had won a surprising victory that day, they were forced to abandon the system immediately due to the Covenant knowing its location, moving out their SSR stations and personnel to another secluded location away from the frontlines. Marco expressed interest in learning the identity of the unknown personnel who had taken out several Covenant ships, and was surprised to find any data on them to be either missing or heavily classified. In spite of this mystery, both he and the rest of Sigma were pleased to have successfully won a victory against the Covenant, one of few as their foe slowly conquered the Outer Colonies.
===Beta Taurius II Campaign===
Main Article: Beta Taurius II Campaign
In early 2538, Sigma Team were assigned to a force led by the famed Admiral to assist the beleaguered UNSC forces there. Cole's fleet quickly gained the advantage in orbit and quickly deployed the SPARTAN-II team groundside to help where the fighting was thickest. Marco joined Wulf and Kane in an infiltration mission behind enemy lines shortly after their arrival, the trio successfully getting inside a heavily fortified enemy camp and assassinating a Sangheili general before escaping unseen. These operations would carry on for some time, until Sigma was recalled for a campaign situated in the arctic region of Beta Taurius II. Here they fought on the frontline against a well-organised and equipped Covenant army in several desperate battles. It was largely through Spartan intervention that the UNSC forces were able to hold their ground for so long, particularly with the space battle above being evenly matched.
Once the campaign began in the planet's northern polar region, Sigma were reunited to help lead the assault against an entrenched Covenant encampment there. While a large armoured company held up the bulk of enemy forces, the Spartans and a number of Orbital Drop Shock Troopers were covertly deployed by a nearby ice shelf, climbing above the encampment to scope it out before the eventual assault. It was revealed that they had used their and a to conceal a CCS-Class Battlecruiser above the site, which was deploying hundreds of troops to overwhelm the UNSC forces below. Marco, Amy, Wulf and Nef were sent to take out the spire with C-12 charges while the rest of Sigma and their ODST comrades caused havoc around the Covenant encampment. The eventual plan was to call in for support from Admiral Cole's ships to hit the battlecruiser once its shields came down. Marco's group were successful in their endeavour, bringing down the spire onto the enemy camp and killing hundreds of foes in the process. As Cole's ships neared their location, the Spartans regrouped with their comrades on the camp's outskirts and were evacuated via Falcon. The allied ships tore the battlecruiser to pieces with targeted MAC rounds and scored a victory for the UNSC that day. 
Sigma Team would spend several months enduring hard fighting on Beta Taurius II as Covenant and UNSC reinforcements battled over the colony world. Even with the legendary leading the defence, the Covenant fleet was eventually able to break the human lines and began to glass the planet. The Spartans, who had been engaging in bloody trench warfare for some time in the southern hemisphere, were given priority for immediate evacuation. Marco was greatly displeased when the first Pelican to arrive demanded that Sigma board it rather than the Marines who had been worn down by the constant fighting. Nonetheless, he followed orders and left the planet with his comrades. Sigma Team was taken aboard the following the end of the lengthy battle and commended by Admiral Cole personally for their efforts in trying to secure the colony world. Though the UNSC were defeated, they had inflicted massive casualties to their foe in the process, largely in thanks to the efforts of Sigma and several other SPARTAN-II teams on the planet. Even so, Marco was uneasy following the loss of the planet, which gave the Covenant a chance to begin attacking Inner Colony worlds. 
===Raid on the Umbra Tempestus===
In December of 2544, Sigma Team was alerted to an attack on the Umbra Tempestus, an older Hillsborough-class Destroyer being used to transport important supplies to staging points for the UNSC Navy. Due to the remote location in which it was ambushed an Insurrectionist attack was not ruled out, though ONI was unwilling to risk a vessel with navigation data leading to Earth and the Inner Colonies being taken by a possible Covenant force. As such, the entire Spartan Team was dispatched on this vital mission with orders to secure any navigational data and to scuttle the Destroyer if necessary.
Arriving with a Battlegroup of six ships, Sigma Team were deployed via Pelican dropship and though an initial scan revealed that one the ship's hangar bays had been left open, giving them an entrance to land. After Marco and Wulf expressed their concerns after getting a bad feeling about the situation, Fenn had Amy, Resk, Kane and Nef remain aboard their dropship with orders to circle round and secure secondary access points to the Umbra Tempestus. With Marco taking the lead, the rest of Sigma moved deeper into the vessel, which had lost all power besides its most basic life support systems. As the ship's elevators were non-functional, the Spartans were made to traverse the length of the vessel and utilise maintenance corridors as they moved towards the upper decks.
Eventually reaching the Destroyer's bridge, the Spartans found that the Umbra Tempestus' entire computer system and navigational data had been wiped clean by the crew, with signs of battle marking the area. Upon discovering evidence of severe plasma damage nearby, Marco confirmed that the ship had indeed been attacked by the Covenant. Thankfully, it seemed that the crew had deleted their NAV data, though the vessel was seemingly irreparable and the mysterious circumstances in which it was found made Marco and his comrades suspicious. Fenn immediately gave the order to destroy the vessel, and as the Spartans prepared to set up detonation charges the power re-activated, revealing dozens of heavily-armed SpecOps Sangheili who had hidden along locked corridors and prepared to ambush the supersoldiers.
Though they were taken by surprise as a sudden mass of Sangheili attacked them, Sigma Team held their ground on the ship's bridge and set up a killzone across every possible entrance. However, their limited ammunition and the fact that it was a dead end meant that they could only fend off their foe briefly. Marco and Jax took it upon themselves to cover the main entrance, taking swords from fallen Sangheili and engaging in a bloody melee while Jacob got to work at one of the Destroyer's main stations. While they had been thorough in sabotaging the Umbra Tempestus' systems, the Covenant had made enough errors in rerouting the ship's systems for the SPARTAN-II's to exploit and turn against them as they deactivated the ship's artificial gravity. In the brief time it took their ambushers to adapt, the Spartans took their chance and made a break for the vessel's lower decks and their hangar, signalling for backup from the rest of Sigma as they went.
En-route, it became clear that the Covenant had planned this operation well in advance. Marco and the others were hit numerous times with glancing shots from plasma weapons, though after their initial rush the Sangheili were wary of engaging the Spartans in close quarters combat. As they moved downstairs, a nearby wall was blown apart by a team of enemy Rangers, who had hidden in a set of maintenance tunnels and attempted to drive Sigma out of the airlocks. As he pushed Wulf into an alcove for cover, Marco was suddenly hit thrice by blasts from a and thrown across the corridor. With most of his back and right side horribly scorched, the Spartan was rendered immobile and in intense pain while Jacob-076 dragged him out to safety. Marco struggled to remain conscious, using his left hand to fight back with an M6D Magnum.
While pinned down yet again, Sigma's proximity to an airlock would have given them an excellent avenue of escape were it not for Marco's heavily-breached MJOLNIR suit and injuries making it impossible for him to engage in EVA activity. As such, Fenn radioed for Kane and the others aboard their Pelican to move directly outside the airlock and open the dropship's rear hatch for a quick extraction. While Jax, Wulf and Jacob ensured that any attackers were kept at bay with sporadic rifle fire, Marco was tied to Fenn with a length of cable for what would be a very short trip through space. It did not take long for their comrades to arrive, and after a brief moment of preparation the Spartans opened the airlock and leapt into the Pelican's waiting compartment. The moment Sigma Team was clear of the Umbra Tempestus the order was given for the rest of the fleet to open fire, tearing the Destroyer apart and killing the remaining Sangheili as they attempted to escape aboard a small ship in one of the other hangars.
The attack and Marco's near-death experience made it clear that their foe had moved far beyond their usual strategy of relentless assaults and the occasional infiltration mission, with several members of Sigma convinced that the Umbra Tempestus trap had been set for the sole purpose of eliminating the Spartans. Marco, who lost consciousness before they returned to the fleet, underwent a number of surgical procedures to deal with the severe plasma burns incurred during the mission. While there was thankfully no permanent damage, save some severe scarring, his MJOLNIR suit's systems were irreparable and the armour had to be scrapped after thirteen years of usage. Several other members of Sigma had begun to feel the wear and tear on their own suits after so long in the field, and with the advent of a number of important technological upgrades the SPARTAN-II's decided to take on improved, more heavily-armoured MJOLNIR systems as the Inner Colony Sieges began. 
===Fall of Kurovan===
In 2545, news arrived that a sizeable Covenant fleet was on its way toward Kurovan, a heavily populated planet in the Inner Colonies. Though this was one of their foe's earliest assaults this far into Human-controlled space, the UNSC had been shoring up the planet's defences and had Sigma on standby in orbit when news of an impending attack arrived. For two days, the Spartans were tasked with overseeing the evacuation of civilians from Kurovan's major cities while the Covenant fleet attacked the system's outlying planets, which had been left to fend for themselves. When they moved to attack Kurovan itself, Marco was in the capital city alongside Amy-133 and Resk-063, escorting a group of VIP's to their personal extraction craft. As they moved down the exterior of a skyscraper in an elevator, Banshee fire from the invading army struck the building and sent their car plummeting to the ground. While the Spartans were mostly unharmed thanks to their armour, their escortees were killed in the crash, leaving them to await further orders as a massive Covenant force invaded the capital.
While the invaders had a clear numerical advantage, the cramped city streets slowed their advance as UNSC forces set up chokepoints at key junctions and established proper defensive lines around key locations. The local headquarters for the Office of Naval Intelligence was one such building, and had come under heavy attack from enemy troops almost immediately. Receiving a call from assistance from Fenn-145, who had been guarding the facility, Marco's team moved quickly to assist their leader. En-route, they linked up with allied forces, including Whiskey-04, and helped clear a path through hordes of Covenant infantry as they moved across the city. With the battle in orbit not going well, enemy reinforcements continued to pour in and made it difficult for the Spartans to hold any ground against seemingly overwhelming odds. 
Linking up with Wulf-041 in an abandoned hotel, Marco and the others were thrust into a prolonged firefight across a heavily-contested plaza that the Covenant were trying to turn into a staging area. With only a few dozen battle-worn Marines to back them up, the four Spartans managed to inflict heavy casualties on enemy troops and were on the verge of turning the tide of battle when a column of Wraith tanks entered the fray, raining down plasma mortars on the surviving UNSC troops. Forced to split up, Marco and Amy took cover in a blown-out building as enemy marksmen kept them pinned down, and were unable to move until Wulf eliminated their attackers. With little time left, Amy constructed a makeshift IED using what little equipment they had left and set it to detonate while Marco distracted the Wraiths by running out into the open. Narrowly avoiding death as he sprinted across what remained of the plaza, he watched as Sigma's explosives expert tossed out a bomb disguised within a stuffed children's toy beneath the enemy tanks and detonated the device. The resulting blast eliminated three of the heavy vehicles and blocked more enemy vehicles from entering the area. Impressed at his comrade's ingenuity, Marco and the others used this opportunity to flee. 
While they initially continued heading towards the ONI building, another transmission from Fenn changed Marco's orders as he dispatched the Spartans to regroup with the rest of Sigma Team at a nearby command post while Whiskey-04 secured the building. Though they had been able to inflict severe casualties on the enemy, it had become clear that Kurovan would soon fall to the Covenant, and all its defenders could do was ensure that as many people escaped as possible. While Sigma had a dedicated transport waiting for them outside the capital, they chose to stay and fight as long as possible. Splitting into several groups once more, Marco joined Jax and Nef in leading a counter-attack against the Covenant using with the intention of destroying an |RCS-class cruiser currently disembarking troops near the city limits. While a tall order even by Spartan standards, Marco accepted this mission willingly and soon set off on a rampage against the enemy. With seven heavy tanks and numerous Warthogs backing them up, the strike force soon pushed through enemy lines, supported by Shortsword bombing runs against any Covenant forces trying to intercept them. 
By the time they reached the cruiser, the battered remnants of their attack force disembarked and used the warship's gravity lift to board the vessel, fully aware that it likely contained hundreds, if not thousands of Covenant soldiers. Fighting with stolen enemy equipment, Marco and his allies blew their way past numerous security doors, keeping up a frightening momentum that only a Spartan could accomplish against the ship's defenders. They soon reached the bridge, where a surprised Sangheili Shipmaster challenged Marco to single combat. Taking advantage of the alien's sense of honour, Marco fought the sword-wielding alien with only a combat knife, but was soon able to outmaneuver and badly wound his opponent before signalling for Nef to execute the enemy leader. With the cruiser seized but with no knowledge on how to operate the craft, Marco's group forced a group of terrified, surrendering Unggoy to assist them with the controls and after gaining some rudimentary knowledge of how to pilot the warship, set it on a collision course with another enemy cruiser that had set down over Kurovan's capital. Pleased that their work was done, Marco and his two allies - the only survivors of their boarding party - quickly moved to the hangar and stole several Banshee craft before escaping.
Marco, Nef and Jax soon contacted the rest of Sigma Team, who were participating in the defence of the Kurovan Central Spaceport after using explosives to destroy the ONI headquarters. They soon moved to assist, providing valuable aerial support for some time while the last military and civilian transports fled the doomed colony world. With nothing left to defend on Kurovan, the nine members of Sigma Team quickly left the city alongside Whiskey-04's survivors and managed to escape mere hours before the Covenant began to glass the planet. Upon seeing his comrades, Marco expressed his surprise that they had made it through such a battle with only superficial injuries, considering the amount of times they had come close to death in the planet's defence. While Kurovan had been lost, the heavy enemy losses brought about by Sigma's actions were later considered one of the finest examples of Spartan tactical prowess in the war.
===Battle of Draco III===
Main Article: 
Shortly after fighting on Kurovan, Sigma were dispatched to Draco III, which was being used as a staging area for UNSC forces. When they arrived aboard the UNSC Bright New Day, they discovered that the planet was already under attack by Covenant forces. At the command of Captain Uriah Maxon, the Spartans were deployed via SOIEV while the frigate moved in to assist the defence fleet in holding off the Covenant invaders. The Spartans landed in the city of New Albany, and swiftly regrouped before assessing the situation. At this point in the battle, the Covenant forces were pressing into the city, overwhelming the UNSC defenders there. Marco was dispatched alongside Wulf and Nef to defend a nearby array of ground-based MAC guns while the rest of Sigma set up ambush points for incoming enemy forces. As they reached the first cannon, it was suddenly destroyed by plasma charges as a Sangheili SpecOps team ambushed the Spartans.
The trio immediately engaged the enemy special forces, who despite their active camouflage were hopelessly outmatched by the supersoldiers. It was here that Marco first crossed paths with Felo 'Ranakee, who was then a Major in the Covenant Military. The two briefly engaged in hand-to-hand combat before the Sangheili was forced to retreat alongside the remainder of his forces, though his skill and resilience genuinely surprised Marco. Though the enemy had been driven off, the gun was a smoking ruin, prompting Marco's team to regroup with the rest of Sigma at the city waterworks. The rest of Sigma had brought the Covenant advance to a standstill after Amy-133's expertise with explosives led to the destruction several city streets, blocking enemy tanks and forcing their foe to engage in costly close-quarters combat across nearby buildings. However, the sheer number of Covenant troops and dwindling ammunition forced the the Spartans to retreat, setting various traps along the way. While scouting ahead through the waterworks, Marco encountered an ODST squad led by Captain Henry McNair, who had retreated from their emplacement in the outer city after their barricades were overwhelmed.
Upon meeting McNair, a man who had a strong dislike for Spartans, Sigma was ordered to defend the city spaceport, which had come under heavy attack by the Covenant. Though Marco and several others voiced their concern that they were being sent on a possible suicide mission, Fenn dismissed their complaints and the team set out on foot to assist the UNSC forces there. Upon reaching the spaceport, Marco and Wulf quickly dispatched a group of Hunters while the rest of the team moved inside to check on the dire situation. After a short conversation with a Marine NCO covering the evacuation, it was discovered that a third of the transports had been destroyed already, and those that were able to escape the planet only did so due to the defence fleet's actions, led by the UNSC Pride.
Outside, Marco met up with another unit named Tango Six, which commanded by Captain Kryss-216, a SPARTAN-II Class II. As she outranked the other Spartans, she was led to the command centre to meet with Fenn-145, who had assumed control of the defence efforts and was helping to direct fleeing ships away from the planet safely. SPARTAN-216 explained that a Covenant Scarab was on its way to the spaceport, and would easily overwhelm the defenders if not stopped. So, Marco, Kryss, Amy, Nef, Jax and Wulf set out across the city to stop the Covenant assault vehicle in it's tracks before it reached them. Though the narrow streets of New Albany had impeded the progress of enemy vehicles before, it posed no such threat to the Scarab, which simply clambered over or destroyed buildings in its path. As such a plan was made to stage an ambush. Kryss would lure the Scarab onto the highway, utilising the speed and manoeuvrability of her motorcycle to stay ahead while Amy, Jax and Wulf would set explosive charges on the side of a weakened building to collapse it on the heavy assault vehicle. As a contingency plan, Marco and Nef would trail it in a Warthog and look for an opportunity to board the Scarab if they saw an opportunity. 
The trap went ahead almost exactly as planned. The Scarab pursued Kryss onto the open highway and moved right into the path of the building, which after detonation crippled two of its legs. As it struggled to free itself from the wreckage, Marco and Nef clambered aboard and fought off a group of Sangheili before destroying the core. The two had just enough time to escape before the Covenant war machine detonated, taking out a good chunk of the highway. With their mission complete, the Spartans fell back to the New Albany spaceport, which had come under attack by fresh Covenant troops that had been deployed directly into the city. Arriving back in time to fend off a wave of attacking enemies, Marco and the others learned that New Albany was the only remaining city on Draco III still under UNSC control; others such as Karnak had been easily taken after Covenant forces overwhelmed the UNSC defenders there. This also meant that the city was one of the only remaining evacuation sites left on the planet. With the last civilian transport launched, along with most of the remaining Marine forces, The ten Spartans and remaining ODST's of Tango Six set out for a third evacuation point in the mountains outside New Albany, where a single ground-based MAC still functioned.
Taking the remaining Warthogs and Kryss' motorcycle, the group fled the city through the waterworks, rigging the spaceport to blow by overloading a nearby fusion reactor used to power the area. Not long after leaving the New Albany, an emergency transmission was picked up, emanating from a reactor complex in the wilderness that powered the MAC. It was coming from Echo 1-1, a platoon sized force of ODST's from the 105th regiment commanded by Captain McNair, who was making a stand there despite being massively outnumbered and outgunned by an entire Covenant Legion. Responding to the transmission, the Spartans drove off Covenant scouts near the complex before getting inside, where they met with the Captain and his ODST's. There were just under forty Helljumpers defending the vital facility, nowhere near enough to even put up a solid fight to the incoming Covenant forces. After a brief argument with Kryss, whose Naval Captain rank superseded McNair's ground one, the Spartan ended up allowing the veteran soldier to direct his troops while she attempted to hail any UNSC forces that remained on Draco III. This was largely done to placate McNair, who made his dislike of Spartans very clear, and would be needed to keep his platoon in line. 
Marco accompanied Nef in placing Lotus anti-tank mines outside the base, and argued about the fact that this new Spartan - a fifteen year old- was commanding them in the field. While Marco had little problem with following Kryss, who had proven herself as a capable combatant in New Albany, Nef voiced his concerns about the younger SPARTAN-II's experience, especially in a situation where the Spartans would possibly have to resort to long-term guerilla warfare. Marco dismissed these thoughts, stating that if Kryss had been trained as they were, then she would have no problems keeping up with her older peers. Returning to the base, the two Spartans were ordered to join Jax and Kryss in defending the main reactor building, backed up by half a dozen ODST's. Kane and Jacob would provide sniper cover from the roof while the rest of Sigma and Echo 1-1 drew the Covenant towards the secondary reactor building, which had been rigged to blow by Amy. In the armoury, a had been discovered by one of McNair's men, and plans were made to detonate the device if Covenant forces overwhelmed them completely. Marco suggested that he or one of the other Spartans should carry the device for safekeeping, but McNair declined and kept the nuclear weapon with his trusted subordinates. 
The complex soon came under attack as a wave of banshees bombed the outer walls, covering groups of advancing infantry. Though many were shot down by the defenders the Covenant fliers managed to destroy large sections of the wall and main gate before retreating. Marco took down several Sangheili attempting to infiltrate the main facility before moving to help Nef and Kryss fight off several Hunter pairs at the main entrance. His timely intervention distracted the powerful creatures long enough for Nef to bring them down with several well-placed shots from his Spartan Laser. Though the Spartans and ODST's were inflicting massive casualties on their attackers they were still hopelessly outnumbered. Sending out an emergency hail again, Kryss was able to contact the UNSC Bright New Day, which had been supporting what remained of the human fleet in orbit.
Captain Maxon immediately sent support down to the surface of the planet in the form of several wings of bombers, which served to slow the massive force down as they bombarded the area outside the complex and killed hundreds of Covenant troops. However, It was discovered that another Covenant army was en-route, having been diverted after news of 'Demons' fighting on the ground had spread. Seeing that there was no way of holding the facility any longer, Fenn ordered Sigma to retreat, covering the surviving ODST's as they made their way to the vehicle depot.
The Fury tac-nuke was in the hands of Lieutenant Mira Reyes, McNair's second in command. Her team, who had been situated in the secondary reactor did not respond to McNair's order to activate it on a timed charge. The ODST Captain and Marco moved to investigate, only to find the troopers slaughtered by Iroe 'Nemokee, a Sangheili Officer leading the attack. Engaging him and his bodyguards, Marco was almost defeated by the accomplished swordsman before McNair saved him by stabbing the Sangheili repeatedly with a combat knife. This gave the SPARTAN-II enough time to move away and acquire a weapon, though McNair was gravely wounded as his opponent slashed him several times and dismembered his robotic arm. Marco was able retrieve a MA5C rifle and opened fire, wounding the enemy Officer and forcing him to retreat out of the building. McNair refused any help from Marco, getting himself to his feet in spite of his grave injuries. Taking the tac-nuke from his dead comrades, the veteran ODST ordered Marco and everyone else to get away from the area before the device was activated. Marco fled the complex and was picked up by Kryss on her motorcycle and joining the other Spartans and ODST's of Echo 1-1 and Tango Six in their retreat into the mountains.
As the surviving ODST's of McNair's platoon reached the entrance to the mountainside base, several Seraph formations attacked, bombing the area and killing most of them. By the time they reached the top, there were only a few dozen survivors, Spartans included. Jacob-076 get to work on opening the large steel doors that led into what had once been a titanium mine, leaving the others to give him as much time as possible. With dwindling ammo supplies, Marco acquired a missile launcher from a fallen ODST and used it to kill an approaching Hunter pair before expending his last shot on an incoming Banshee. Though the Spartans performed superbly in close combat, slaughtering the Covenant infantry and using their weapons against them, it would only a matter of time before numbers and superior fire overcame them. As Marco and his comrades began to fall back, Jacob opened the door for a short amount of time and sabotaged the control panel so they would not be followed. 
All of Sigma made it inside before the doors shut, along with the few survivors of Tango Six under Kryss. Three ODST's got inside as well, though one died of her wounds shortly after, leaving Ash Mitchell and Mal Roberts as the only living members of Echo 1-1. Marco conversed with them briefly, reassuring the rather shaken troopers that they were not at fault for the deaths of their unit and that survival was a priority. As they began to make their way through the interior of the mine the mountain shook as McNair's tactical nuke detonated, destroying most of the valley and obliterating a Covenant Legion there. Fenn was able to establish contact with Captain Maxon once more, arranging for a Pelican pickup at the exit of the mine. The group was able to make it out in the early hours of the next morning. 
Upon reaching the extraction zone, Marco learned of the slaughter that had occurred within Draco III's other cities, and was disturbed to learn that the UNSC had seemingly abandoned the people there. In retaliation, several had been dispatched to destroy the remainder of Covenant forces while a second UNSC fleet drove off enemy ships. Sigma boarded their personal Pelican, saying goodbye to Kryss-216 and the ODST's as they headed back towards the Bright New Day. For Marco, Draco III had been an incredibly difficult battle that forced him to face the reality that no matter how powerful, the Spartans could never save everyone. Nonetheless, the fact that they had saved most of New Albany's population gave him some comfort as news of Covenant atrocities on the planet began to spread.
===Battle of Gress===
In early 2546, Sigma was based on Gress, a large, industrial-based colony and site of an extensive dig into unknown alien ruins. While there, the SPARTAN-II's were informed of an unusual object that had been recovered there: A large crystalline shard that, when scanned, gave very unusual readings, prompting the scientists there to believe that it should be taken for study on Reach. Before arrangements could be made for transport, reports came in of a small Covenant fleet entering the system, sending Sigma and the UNSC defenders on Gress into high alert. Due to the limited defences that the UNSC had in space, the human fleet retreated around the other side of the planet, planning to make quick strikes against their enemy while covering the civilian evacuation ships. Surprisingly, the Covenant did not attempt to glass Gress, instead deploying hundreds of landing craft to the planet. 
Marco, who was stationed in a remote ONI base with Resk-063 and Jax-007, was tasked with the protection of this crystal as Covenant dropships began to land in the area. Along with Whiskey-04, the three Spartans boarded a , which would transport them to a spaceport, hundreds of kilometres away, where the rest of Sigma were covering the evacuation on the ground. Moments after they set off, Marco noticed that their pursuers had all but abandoned the base, over a dozen Phantom dropships chasing them. Rather than destroy the train, as they could have quite easily done, they began to deploy a number of . Correctly guessing that they were after the crystal, Marco left it in the capable hands of Major John Ackton and the ODST's before joining his comrades in fending off the Covenant boarders. 
As the first few enemies managed to break through into the armoured train, they were met with heavy machine gun fire, courtesy of Resk, while Marco and Jax (against the former's better judgement) climbed onto the roof to prevent their foes from getting to Whiskey and the crystal. There, the two Spartans fought against numerous Sangheili for some time, their magnetised boots keeping them from falling as the train hurtled towards the spaceport. Eventually, a group of Sangheili SpecOps warriors arrived, proving to be almost a match for the two, one nearly overwhelming Marco, had it not been for Resk's timely intervention from below, the bigger Spartan pummelling the Sangheili and driving the others back while Jack defended his comrades with a pair of captured energy swords, butchering any who came near.
With the Spaceport in sight, a number of Pelicans and AV-14 Hornets arrived to escort the defenders inside, forcing their surviving enemies to retreat. Arriving in the transportation terminal with the crystal and no casualties, Marco linked up with the rest of Sigma. However, before they could board one of the remaining spacecraft, several emerged from slipspace, decimating the UNSC Fleet above the planet. With their forces scattered, and an army of Covenant descending on them, Sigma was forced to make a hasty retreat through the city, leaving the spaceport to be overrun as they were directed to a landing zone not far away. The sheer amount of Covenant, however, proved to be too much for the already outmanned Marines, the LZ being ovverun before the Spartans could reach it. With enemy forces closing in, Fenn-145 revealed that he had been given possession of a for use in the most dire of circumstances, as orders had come down from the highest level not to allow the crystal to fall into enemy hands.
As the entirety of Sigma had no wishes of blowing themselves up, Marco suggested that they could drive the Covenant back with the threat of destroying the crystal before using the HAVOK in their favour. With little time remaining, Marco spoke over an open COM channel, threatening the Covenant and forcing them to retreat while the Spartans made plans to escape. They were able to find a couple damaged, but serviceable Pelicans, which had been shot down earlier. Nef-015 and Jacob-076 were able to repair it as the others provided cover, Covenant infantry beginning to make their assault in spite of Marco's warnings. The team split up into the two dropships in order to confuse their foe, and took off out of the city. Knowing that they would be relentlessly pursued until the Covenant obtained the crystal, Marco dropped it, HAVOK attached, into a forest while they fled into the mountains. 
Marco detonated the nuke, destroying the crystal and utterly obliterating most of a Covenant Legion that was after it. As they had only just gone beyond the blast radius, their Pelican went down once more, Nef managing to pull off a crash landing above the remains of the forest. Having lost contact with the other Pelican and all other UNSC forces, Marco's group remained there for over an hour, watching the Covenant glassing the distant city while they attempted to repair a long-range radio. They were eventually contacted by the UNSC Albumasar, one of the few remaining ships in orbit. The cruiser had picked up the other Spartans, and dispatched a single dropship to evacuate the others from the planet before Covenant ships could locate them. While on patrol, Jax and Resk stumbled across a vengeful Covenant force out for blood, and were forced into a hasty retreat towards Marco and the others, who in turn were making their way towards the LZ.
The Spartans were picked up, just in time, by the Pelican, and successfully evacuated from Gress. In spite of the fact that they had lost a potentially valuable alien crystal, Marco was content with the fact that they hadn't allowed the Covenant to obtain it, either. However, they had lost another colony, and thousands of innocent lives in the process, something that Marco and the other Spartans found themselves dealing with on a surprisingly regular basis. For his actions on Gress, Marco was given a long-overdue promotion to , the same rank the rest of his comrades had been granted two decades ago.
===Siege of Fargad===
Main Article: Siege of Fargad
In September of 2547, Sigma Team were called into action on the Inner Colony world of Fargad after a Covenant invasion force arrived in-system. As they were already the colony world, testing new MJOLNIR armour variants, the Spartans were among the first to respond as enemy landing parties deployed thousands of troops against the UNSC defenders. As one of the last remaining military centres aside from Earth and Reach, Fargad was a critical planet in supporting the war effort. The Spartan team was deployed to assist the 7th Infantry brigade of the Army forces on the planet in a massive assault on Covenant landing zones in order to buy the evacuating cities more time. In a critical mistake made by Colonel Brandon Walters, the Army commander on Fargad, the 11th mechanised brigade was all but wiped out in the initial assault on the original landing zone, leading to the discovery of over a hundred thousand Covenant troops all across the continent, nearly three times more than army recon had anticipated from a single ship. Reports from Rear Admiral Hsu, the UNSC Naval commander, verified that several Covenant cruisers were deploying troops from orbit rather than set up a landing zone. As such, half a dozen settlements were obliterated on the first day as the Covenant advanced towards the highly populated cities on Fargad.
Brigadier General Richard Mack Senior, the de facto UNSC leader on the ground, initiated a greatly revised and better planned strategy, one that would buy the defenders much more time. While the bulk of the Covenant army advanced towards one of Fargad's central cities, Antolia, elements of the 91st and 104th Marine regiments would strike from the mountainous region that encircled the area, catching the enemy off-guard with hit-and run attacks. Meanwhile, Sigma and the remainder of Army forces would launch an all-out attack with hopes of crushing the enemy legions there. This strategy proved to be a success, with UNSC forces and Sigma successfully holding the line and decimating the entire Covenant attack force, though not without considerable losses. Though they had achieved a major victory on the ground, in orbit the UNSC fleet was pushed back, Admiral Hsu ordering for the remaining battlegroups to split up and circle round for another strike at the Covenant attackers, hoping to draw some away from the planet. This allowed the carrier, Glorious Victory, to enter Fargad's atmosphere and rain plasma fire down on the humans below. Once again, the UNSC issued a full retreat into the city, which was still defended by several ground-based MAC guns and mass drivers. 
thumb|290px|right|Marco assisting UNSC Army soldiers during the Siege of Fargrad
Sigma split up once they arrived, Marco joining Wulf, Amy, Jax and Nef in the defence of the unprotected city harbour. It was there that they were placed on a 'Wet Navy' ship, a rare sight during the Human-Covenant War. The commander of the antiquated ship, Admiral Han Kurtz, was charged with defending Antolia city from the western flank. Shortly after boarding, Marco was surprised to find twelve other Spartans, making up teams Upsilon and Tau already there. This marked the first time Sigma had directly worked with SPARTAN-III's, Marco and the others having been vaguely aware of other supersoldiers in the field beforehand.
After a brief introduction, the ship received a message that a Covenant army, thrice the size of the previous one, was on it's way to the city. While having seventeen Spartans on board was useful to the wet navy ship, the supersoldiers would be needed elsewhere, several falcons being sent to pick them up. While conversing with the younger Spartans, Marco was ambushed by a Sangheili assassin and would have died were it not for the timely intervention of Martin-A136. While the others searched for the assassin's comrades, a quick-thinking ODST named Bill Cross noticed another cloaked Sangheili planting plasma charges on the side of the ship and quickly eliminated it. Upon closer inspection, it was revealed that this particular elite was an , sent to spy on the humans. 
However, there was little time to ponder its presence, as the first wave of Covenant attackers had struck the city. Surprisingly, the enemy had not attacked via the bay, allowing the Spartans to relocate to other areas while Admiral Kurtz' ship stood guard. Marco's group met up with elements of the 91st regiment in downtown Antolia, saving them from a wraith attack. Acquiring a Scorpion tank dispatched via Pelican, the Spartans proceeded to wreak havoc in the city, punching though enemy lines and allowing UNSC forces to push back while consolidating and entrenching their own positions further in. By the time the battle had reached it's fifth day, the Covenant had gained a definite advantage on the ground, and had destroyed nearly two thirds of the UNSC fleet in the Fargad system. The evacuation, on the other hand, had been a complete success, with over 90% of the evac ships escaping unhindered. Marco and Sigma had been redeployed to defend Storm Base, a facility which was acting as the HQ for Richard Mack as he directed ground assaults on the planet. Admiral Kurtz had sacrificed himself by ramming his beloved ship into a scarab as it attempted to get through the city harbour, killing a mass of enemy troops before that with the onboard cannons. 
After Antolia fell and it seemed that the Covenant would overrun the base, Sigma set out to lead the enemy away from the base, playing a game of cat-and-mouse with the approaching army, hit and run tactics, as well as insulting messages broadcast on unencrypted enemy frequencies, drove a great deal of forces in pursuit of the Spartans, who were able to flee toward the mountains. The 13th Engineers, also known as 'Lucky Company', had prepared an ambush there, using several FENRIS tac-nukes to bring down half a mountain on the enemy. In the ensuing confusion, Sigma launched an assault on the survivors, Marco personally killing their Field Marshall, Ran Tur 'Ontokee, as he attempted to flee. The Spartans moved back to Storm Base, where Upsilon and Tau had arrived via Pelican to extract Mack and move him to another city, one that had yet to fall to the Covenant.
The seventeen Spartans were tasked with the defence of the base while all high-ranking personnel were evacuated. Though several UNSC army brigades under the command of Colonel Walters were still engaging the enemy on other parts of the planet, the bulk of Covenant troops, still enraged from the destruction of their Legion and Field Marshall, were diverted towards the base, with orders to wipe out the 'demons'. The base, despite being hastily built from when the Covenant attacked, held out for some time, with Marco and the others cutting down waves of enemies, fighting well into the night. By dawn of the fifth day of Fargad's siege, Sigma and the others pulled back while shortswords dispatched from the UNSC Bright New Day carpet bombed advancing enemies, giving the Spartans time to escape towards the capital, where Mack Senior was marshalling the surviving UNSC forces.
Even with the considerable advantage of having SPARTAN support, it became clear that the UNSC were losing. News arrived that Colonel Walters had been killed in a banshee strike, while Rear Admiral Hsu's ships were still, if barely, holding the line. As with Antolia, Fargad's capital, New Istanbul, had been heavily fortified, the defenders ready for street-by-street fighting in order to hold off the Covenant as long as possible. After giving an inspirational speech to the remaining human forces in the city, Mack Senior took full charge, sending Sigma to the frontlines while the last few transport ships departed from the planet. The plan was to have several UNSC ships ready to pick up the remainder of the soldiers before initiating a full retreat outsystem.
When the Covenant attack came, the humans were at least motivated this time. Marco and Wulf led a platoon in the lower streets, blocking several and forcing the Covenant to reroute their tanks. By this time, however, the remaining Covenant ships had regrouped following their heavy losses and were getting in formation to glass the planet, city by city. With most of the UNSC fleet driven off, they would have little-to-no opposition in wiping out the humans on Fargad. As the Spartans were slowly pushed back, they received a distress signal from Mack's bunker, which had come under attack. Sigma Team stormed the complex in a desperate and risky search for Mack Senior. By the time they had reached the final room, they discovered the Brigadier General alive, along with the ODST squad, Whiskey-04 and his son, the small group having killed dozens in a last stand. 
Escaping the bunker, Sigma and the others rejoined Upsilon Team in the retreat. Just outside New Istanbul, the UNSC Bright New Day had arrived in atmosphere, raining down fire on the Covenant army as it was joined by three other Frigates. The evacuation took four hours, with many casualties in the process, including Admiral Hsu's ship, UNSC Frankenstein, which had gone down firing everything it had at a Covenant capital ship. The thousands who survived were evacuated outsystem, the UNSC remnants fighting their way out until they could execute a safe slipspace jump. Though it ended in a defeat for the UNSC, Fargad being completely glassed shortly after, it had come at a heavy cost for the Covenant. Over two thirds of their fleet had been destroyed, along with a massive number of ground casualties. Also, Sigma Team were able to successfully remove all data pertaining to ONI-run experiments on Fargad, some of which would lead to MJOLNIR armour improvements in the future.
===Battle of Nevarra===
In mid-2549, Marco, Nef-015 and Amy-133 were sent on a mission to assassinate a high-ranking Insurrectionist leader on Nevarra, one of few Outer Colony worlds as yet untouched by the Covenant's relentless advance. The success of the mission was vital, as the death of this leader would break the back of one of the few remaining holdouts the insurrection possessed. Though none of the three chosen for the mission were as skilled as Kane-098 or Jacob-076 with a sniper, they were known for their talent for destruction. Upon infiltrating the base in which Colonel Markus Jensun, was residing, the Spartans began to plan their assassination. As he was particularly well-protected within the heart of his base, they would launch their attack as the Colonel as he gave a speech the next day, killing him and his senior staff and destroying any other military assets before exfiltrating.
Marco was assigned to place the C-12 charges on the reactors which powered the base, as well as on the main landing pads around the base. Nef was the designated shooter, taking his position in an air traffic control tower, which would be empty for the duration of the speech. Amy, as the main explosives expert of Sigma, had set up a large quantity of C-12 around the infrastructure of the facility to be used once the Spartans had made their escape. On the night of the speech, however, something happened that completely changed the plan. Three Covenant cruisers had appeared above the planet, getting past the bulk of Human defences via slipspace jumps, and smashing them from behind. As team leader, Nef ordered the Spartans to regroup outside the facility, watching as an army of Covenant soldiers was dispatched mere miles away from the base, while the other two Cruisers began to glass other parts of Nevarra. 
At first, the Spartans were content to detonate the base when the Covenant reached it, killing as many as they could before exfiltrating and linking up with a UNSC Prowler on the edge of the system. However, further recon indicated that many civilians from the towns and villages nearby were making their way towards the rebel base to find shelter or transport. This was a problem; the Spartans could not kill that many innocents, or let them be butchered by approaching Covenant forces, so a risky plan was made. Infiltrating the base once more, Marco found the Colonel in his war room, discussing plans to evacuate in the three ships they had. The problem was, that they would not have enough room for their forces and the hundreds of civilians. Marco dropped into the room, and despite facing half a dozen men, proposed a deal with Colonel Jensun: The three Spartans would assist the insurrectionists in holding off the incoming army for as long as it would take to evacuate the civilians, and then they would retreat through the surrounding jungle to the location of the Spartan's ship, which at full capacity could hold roughly a hundred people. 
The Colonel reluctantly accepted the plan, more out of desperation than anything else. Amy and Nef joined Marco in the base, where they began to coordinate a defence against the incoming enemy forces. Using their remaining Lotus Mines and C-12 packs (Marco deliberately neglected to tell the Colonel about the hidden charges around the base), the Spartans set the area around the base up as a trap for enemy forces, while the rebel forces set up ambush points up the roads leading to the base. After a few initial skirmishes, a column of Wraith tanks were sent against the humans. Nef, who had climbed a tall tree, was able to take the first few out with his Spartan laser before they zeroed in on his location, forcing him to retreat further up the hill, towards Marco's location. Marco had been keeping enemy infantry pinned down on the right flank, losing many soldiers as he did so. Amy had kept back, along with the Colonel, who was overseeing the evacuation. She would signal to the others when to fall back, and once they had done so, the charges would be triggered.
Marco and Nef, along with a dozen rebels, had been pushed back up near the base's entrance by a large force of Elites, who were attempting to flank them. After acquiring an energy sword from a dead Zealot, Marco cut a bloody swathe through the enemy, Nef and the soldiers assisting him as he pushed Covenant squads back. Upon hearing about the 'Demons' on the battlefield, the Covenant Shipmaster ordered that a Scarab should be deployed onto the battlefield. Unable to hold back the giant walker, the human forces fell back as it, accompanied by hundreds of combatants, cleared a path to the base. 
By the time the Scarab had arrived, two of the three transports had departed, and the third was lifting off. The few working AA guns at the base ensured protection from banshee fire as the few dozen survivors of the battle outside made it back to the base. Waiting until the Scarab had reached the optimal zone, Amy detonated the remaining explosives, crippling the walker. Despite this, Covenant Infantry swarmed over it's burning husk and towards the base. It was time to leave. As the humans fled into the jungle, Marco triggered the explosives that they had set the day before, obliterating the base. The Colonel and his surviving men followed the Spartans to their ship, and got on board. Despite his hatred for the UNSC, Colonel Jensun admitted that he admired the Spartans for their devotion to protecting Humanity and agreed to willingly turn himself in. The three Spartans and the rebel survivors managed to escape offplanet without attracting enemy attention, and escaped the system in a waiting Prowler.
===Siege of Paris IV===
Main Article: 
In November of 2549, Sigma Team were deployed to assist in the defence of Paris IV as part of a supporting fleet that would cover evacuation efforts and secure important sites across the colony in an attempt to hold their foe back. As they split up to cover as much ground as possible, Marco was joined by Jax-007 and Resk-063 in a mission to secure one of the planet's most important orbital stations against enemy attacks. As the facility had been hastily abandoned by its civilian crew the moment Covenant vessels entered the Paris system, its databanks and the information they contained had not been wiped as per the Cole Protocol. The trio of Spartans moved in via Pelican just as a broke off from the Covenant fleet's main offensive line and began to dispatch troops towards them. 
Realising that the enemy was seeking to take over the station and not destroy it, Marco and the others quickly set up defensive positions aboard the space station and used their supply of antipersonnel mines and to ambush the boarders. As groups of Covenant Rangers entered via docking tubes and airlocks, Marco drew them further in by acting as bait, firing towards the alien attackers before retreating further towards the station's command room where Jax and Resk had set up a pair of machine guns. After drawing the scattered boarding teams into their field of fire, the Spartans detonated their explosives and completely levelled a good portion of the station along with several dozen enemy attackers before quickly finishing off the rest. While the Covenant were undeterred and continued to send in troops via Phantom dropship, they soon realised what they were up against and began to withdraw as the Cruiser itself launched an attack on the station. 
As the Covenant saw killing three Spartans as worth more than any navigational data, the trio chose to make their retreat immediately, with Marco acting as a rearguard for his comrades. As they moved through hallways leading back to their Pelican, the Cruiser fired its energy projector towards them, cutting the corridor in front of Marco in half just as Jax and Resk were able to move out to safety. Taken by surprise and lacking any form of EVA gear or a thruster pack, Marco was flushed out and sent flying into space, unable to control his trajectory. While he expended what ammunition he could to slow himself down, the Spartan quickly lost his weapon and was cast adrift, alone and helpless in Paris IV's orbit. As he attempted to contact the rest of Sigma, he discovered that long-range COM systems were being jammed by the Covenant, and had no choice but to await help while the air in his MJOLNIR armour slowly ran out.
Marco would continue to send emergency hails over the course of an hour, growing more and more panicked as time went by. As he drifted through space, he watched the Covenant begin to glass Paris IV and for the first time since his prior near-death experience five years ago began to ponder his own mortality; while he had long since accepted self-sacrifice as simply part of being a soldier during his years of training, Marco was genuinely frightened of dying in such a manner outside of battle and continued struggling to get help as he continued to lose air. Thankfully, Jax and Resk arrived just in time aboard their Pelican, having been forced to take a rather circuitous route to his location to avoid the enemy warship, which had been taken out by a UNSC Destroyer's MAC round earlier. Having been saved with less than a minute to spare, the rather shaken Marco was somewhat relieved to find that they were abandoning Paris IV, and after meeting up with the rest of Sigma Team aboard an ONI Prowler retreated from the system to fight another day.
===Battle of the Hephaestus Array===
Main Article: Battle for the Hephaestus Array
 
In 2550 a portion Sigma Team, along with Battle Group Tempest, was sent to the Olmara system to investigate a series of attacks on UNSC ships in the area by insurrectionists, who were raiding and capturing the vessels. Among the cargo in one of these vessels was several suits of newly-developed MJOLNIR armour that were in transit to Earth for more extensive testing at the hands of both Sigma Team and the Materials Group. Led by Jacob-076, Marco was joined by Nef, Amy and Wulf on this operation. While it was initially believed to have been the work of simple pirates, Marco suspected that an incredibly organised and well-informed group had conducted the raids with the intention of stealing the incredibly expensive MJOLNIR suits for their own purposes.
As the ships drew near the planet Endrin, they came under attack by several captured ships of varying sizes. All but one of these ships were easily destroyed by UNSC force in moments, with the last one fleeing towards the planet. As a Destroyer, UNSC Livingston, pursued the ship close to the planet, it was hit by several MAC rounds and blown apart almost immediately. On the far side of Hephaestus, a large fleet of over eighty Insurrectionist ships was assembled. Most of the ships had either been captured by the Insurrectionists or had been taken. The largest, a Gorgon-class Destroyer that had been among the ships taking the supplies and the armour to Earth. As the Battlegroup prepared to attack, the Insurrectionists sent out a message to the UNSC forces, ordering them to stand down and leave the system. Naturally, they refused and continued on course towards the construct.
Marco was deployed alongside Wulf-041 and Jacob-076 in a bid to destroy the main ship in the array, and kill or capture the Insurrectionist leader. However, although they had not told their superiors, the Spartans knew who the enemy leader was, and that it was very unlikely they would take him alive. Amy-133 and Nef-015 were deployed to assist separate UNSC forces groundside. The first team was sent in with over forty Pelicans, escorted by two Frigates. They took heavy losses as they approached the array, with only twelve of the pelicans surviving, and the Frigates destroyed. The surviving ships landed on the Hull of the ship, and the Spartans, along with several platoons of ODST's entered the ship through the airlocks, intent on finding the Insurrectionist Leader, Jack-085.
The Spartans led the fighting through the ship and towards the bridge. They took heavy casualties as they neared the bridge, and Jacob-076 ordered the surviving ODST's to fall back towards the pelicans, saying that the fighting would end soon. The real reason for him saying that was because he and his fellow Spartans both knew in their minds who the enemy leader was, and wished to keep it a secret from the rest of the UNSC. they entered the Bridge, and made quick work of the bridge crew. However, the Insurrectionist leader was nowhere to be seen. As they took control of the helm, Jack-085, who had been waiting for them, fired a rocket, narrowly missing the Marco and hitting the floor near Jacob, sending him flying. Jack then fled, with Wulf and Marco in hot pursuit. They chased him to the hanger, where Jack boarded a Longsword fighter in an attempt to escape. Marco and Wulf followed him in a stolen Pelican.
As Marco and Wulf departed the Array, a Covenant fleet arrived in-system, engaging both the UNSC and Insurrectionist forces. As they pursued Jack, they were contacted by Jacob, who was attempting to take control of the structure's key systems and promised to hold his ground against enemy reinforcements for as long as he could. Shortly after entering Endrin's atmosphere, Jack's Longsword was shot down by UNSC forces and crashed in an uninhabited area. Certain that he had survived, the two Spartans landed nearby and made their way towards the crash site.
When they got there their quarry was alive and unhurt, protected by his MJOLNIR armour. Jack ambushed the two Spartans, knocking Wulf out and wounding Marco in a furious assault. Narrowly avoiding death, Marco was able to close the distance and disarm Jack, seizing his weapon and slamming him into the dirt. Having seemingly bested Jack, Marco held him at gunpoint as he was contacted by Jacob, who informed him that the only way to defeat the Covenant's powerful assault carrier would be by crashing the damaged Hephaestus Array into it in a suicidal attack. While Amy was en-route to save him, Marco soon realised that his teammates had little chance of making it out alive.
Taking advantage of Marco being momentarily distracted, Jack managed to leap up and grab Marco's gun. Though the two had always been closely matched in training, both were exhausted and Marco would have died, were it not for the Hephaestus Array's sudden destruction in orbit. While shocked as Jacob and Amy's signals vanished, Marco was more surprised when Jack suddenly tore off his helmet and fled, having apparently snapped at he sight of his creation's loss. Once again, Marco allowed Jack to run, and was unable to pursue his former friend as he travelled into the nearby mountains, where what remained of the Array had begun to land. Reviving an unconscious Wulf, Marco signalled local UNSC forces and were airlifted out of the area before the wreckage made the entire area completely uninhabitable. Though there was no evidence of Jack's body and Marco lied to his superiors, telling them that the Insurrectionist leader had died in his fighter's crash. Though he wanted to believe that his friend had died in Endrin after informing the rest of Sigma about his presence, Marco vowed to not let Jack escape him if they ever met again.
===Battle of Cronus IV===
In May 2551, months after the loss of two squadmates, Sigma Team was split into several groups for a short period of time. Marco and Resk-063 were sent to Cronus IV, a largely agricultural colony world in the Inner Colonies that was also home to a testing facility run by the . The two Spartans were testing new MJOLNIR armour variants for usage in the field, including prototypes for the Mark V suit, which would possess a recharging energy shield reverse-engineered from Covenant shielding technology. The pair fought their way through a number of obstacle courses that tested the armour's shield strength and durability compared to previous variants, emerging with outstanding results. Mere hours before Marco and Resk were to leave the planet, a number of Covenant ships arrived in-system, launching an all-out attack on the colony world. 
While the testing facility began to evacuate, Covenant forces began to land nearby, attacking the defenceless farming communities. The Spartans moved out to help the civilians, arriving just in time to rescue a village from a group of Kig-Yar. With limited transport ships on Cronus IV, Marco allowed the civilians to take their Warthog to the local spaceport for evacuation. The pair spent a number of hours moving through rural areas, eliminating Covenant patrols and rescuing people where they could. This was the first live test of the MJOLNIR Mark V's capabilities, the energy shielding coming in handy against the waves of Covenant infantry. Furthermore, the new additions to Marco's suit, such as an up-armoured helmet variant and a Command Network Module, would give him a much bigger advantage in the field than he had in previous years. Once the local communities were safely evacuated the Spartans moved back to defend the testing facility, which had come under Covenant attack.
By the time UNSC Marines arrived on the planet to combat the much larger Covenant force, the Spartans had been defending the base for several hours, Marco utilising a heavy turret to mow down infantry while Resk provided support with an M39 Grenade Launcher. While they had inflicted massive casualties on the ground, the facility's meagre security force had been depleted and Marco seriously doubted that they would hold out for more than a day. The arrival of Seraph bombers and Wraith tanks in the valley below confirmed his fears as the base's automated defences were quickly destroyed, allowing Phantom dropships to deploy troops easier. Resk and Marco fell back into the facility alongside the remaining human defenders and used the narrow corridors as chokepoints to hold of their foe for some time while all relevant data pertaining to Earth and the colonies was destroyed, as per the Cole Protocol. Eventually the decision was made to completely obliterate the facility with C-12 charges rather than allow the Covenant access, the Spartans covering a team of engineers while they set the explosives before retreating to the vehicle bay. 
With barely two dozen survivors remaining, Marco and Resk led a convoy of vehicles away from the base as the charges were detonated, fleeing into the nearby hills under heavy pursuit. There, the Spartans led a spirited defence until several Pelican dropships arrived, scattering the Covenant infantry below with a missile barrage before picking up the survivors. While Cronus IV was quickly glassed by the Covenant, Marco's group were taken to a nearby UNSC Frigate and evacuated from the system. In spite of the colony's loss, the new MJOLNIR suits had passed their first real field test and were soon ready for wider production thanks to the data gathered by Marco and Resk. They were eventually issued to most SPARTAN groups in November of that year.
===Battle of Harpa=== 
Main Article: Battle of Harpa
In March 2552, Sigma Team was stationed on Harpa, an inner colony world mainly used as a staging ground for the UNSC Fleet. The Spartans were taking part in routine training exercises when a sensory outpost picked up three Covenant Destroyers en-route to the planet. Harpa's defence fleet, which consisted of barely half a dozen ships, moved to engage but were quickly decimated by the Covenant's superior weapons after bringing down one Destroyer. While the Covenant were expected to immediately begin glassing Harpa due to it's low tactical value, they instead began deploying troops groundside in an attempt to wipe out the Human populace. 
Marco and Jax-007 were sent to Harpa's capital, Andama, to assist in it's defence while the rest of Sigma covered the civilian evacuation elsewhere. While the initial Covenant assault had been little more than a massacre, the arrival of two SPARTAN-II's and a company of UNSC Marines helped to stem the tide, Marco personally leading a platoon in an offensive that destroyed a dozen Wraith tanks and blocked off a number of roads. The battle soon descended into bloody urban warfare, Banshee and Shortsword strikes levelling entire city blocks as neither side could gain a proper advantage. Even the Covenant's feared Scarab assault platforms did little to change the situation, the narrow streets giving Marco and Jax a chance to board and destroy one while coordinated artillery fire took out two more within Andama. 
The fighting in Andama lasted nearly four days, Marco going without sleep to continue holding the line. The presence of two Spartans greatly raised morale among the Marines there, though casualty rates were still high and victory seemed unlikely with fresh Covenant troops arriving by the hour. Furthermore, they had set up a large encampment on a hill that allowed them to rain plasma fire over the Human-controlled portion of the city. A previous attempt to take it had left Marco wounded, losing the left shoulder plate of his MJOLNIR armour to a plasma grenade that almost killed him. While there were a number of officers in the city that outranked Marco and Jax, the Marines looked to them for orders; the pair were considering initiating a retreat when reinforcements arrived in the form of several , Nef-015, Resk-063 and Wulf-041. This massive boost in firepower allowed the UNSC forces to advance once more, missile barrages eliminating any heavy targets while the infantry moved in and wiped out the Covenant holding the hill. While this appeared to be the turning point in the battle, with Covenant forces in complete disarray, a Covenant Destroyer had moved in and began to glass the city, effectively rendering their victory obsolete. 
Marco and the others were airlifted out of Andama in Pelican dropships, retreating under heavy fire towards Harpa's vast jungles. Sigma's transport was struck by a number of fuel rod blasts, losing an engine and crashing shortly after. While the Spartans survived after locking up their MJOLNIR suits, Wulf-041 had been flung out of the dropship during their descent and landed several miles away. During their search Marco's group battled a number of Covenant patrols; by the time they found their missing comrade he had singlehandedly scaled and destroyed a Scarab as it travelled through the jungle. Once they were reunited, Sigma Team was able to ambush and hijack a Phantom dropship as it moved in to deploy troops, flying north towards HAMMER Base, the planet's main rally point for all UNSC forces.
The Spartans arrived at the base the following morning and met with Fenn-145, Kane-098, and Brigadier General Richard Mack Senior, who was in charge of leading the planet's defence. Marco discovered that the evacuation had been largely successful, with just over 75% of the civilian ships escaping safely. However, the only remaining orbit-capable transport on Harpa was the UNSC Bright New Day, a Frigate that had escaped the space battle and was holding its position above a nearby desert. Mack decided to wait for the last few stragglers to arrive at HAMMER before moving out, even if it meant holding off an all-out Covenant assault on the facility. After catching up on some sleep and having his armour repaired, Marco joined Wulf-041 in organising the defence alongside the nearby mountainside. With two Covenant Destroyers en-route to the base they had very little time to do so, managing to set up a field of LOTUS anti-tank mines and setting up firing positions to hold off the incoming army. The base's only real defence against the ships was an old , manned by Resk-063 and guarded by an ODST Platoon. 
When the attack finally arrived, the defenders came under heavy assault by waves of Phantom and Spirit Dropships, most of which went down before landing; the troops that did arrive either stumbled into the minefield or were cut down by the base's autoturrets. However, this did not stop the Destroyers from deploying a number of SpecOps Sangheili via drop pods to cause havoc and eliminate sniper teams along the mountainside. Marco and Wulf came under heavy attack by one group, the Spartans barely holding them off while more dropships moved in to attack. In spite of the base defences and advantageous position of the defenders, the Covenant forces greatly outnumbered them and could afford to lose waves of infantry if it allowed them to slowly break through the UNSC's defences. Eventually a lucky plasma mortar shot destroyed one of the base's primary generators, taking the autoturrets offline just long enough for the infantry to advance and engage UNSC troops at close quarters. A large number of Drones swarmed into the base through service tunnels and would have overwhelmed the defenders had it not been for Marco's timely arrival alongside a group of Marine ''; they incinerated dozens of the bug-like aliens and forced the others out of the base. 
Though they won several minor victories across HAMMER Base, the facility was compromised after nearly an hour of fighting, Mack ordering a full evacuation after the Mass Driver lost power. With the deployment of Jiralhanae the Spartans faced a tougher battle in the confined quarters of the base, Marco would have died were it not for Resk-063 gunning down an entire pack with his turret. Nef-015 was deployed to initiate the base's self-destruct sequence while Marco and the rest of Sigma regrouped in the vehicle bay; they would escape alongside the survivors through a tunnel that led through the mountains. While their fellow Spartan was successful, he was also badly wounded when a Jiralhanae Chieftain ambushed him and, ignoring Marco's pleas, decided to take down one of the incoming Destroyers alone so it could not pursue his comrades. Sigma Team lost contact with Nef halfway through the tunnel after the Spartan detonated a HAVOK nuke within the Destroyer. Distraught over the loss of a friend and teammate, the Spartans pressed on until they emerged near the edge of the desert where the Bright New Day was stationed. While most of the troops headed straight for the vessel, Sigma moved in to fend off Covenant attackers within nearby ruins. During the ensuing battle, Mack Senior became separated from the main group and came under attack by a much larger Sangheili force. Before Marco and the other Spartans could come to their teacher's aid, he was killed by Shipmaster Felo 'Ranakee. While Jax-007 was able to injure and drive off the Sangheili, the loss of Mack made a massive impact on the troop's morale and sent the surviving UNSC forces into an all-out retreat.
The UNSC Bright New Day was able to leave Harpa safely, though it was cut off before it could initiate a slipspace jump by the surviving Covenant Destroyer. The Shipmaster contacted the ship and ordered the Humans to surrender their navigation data. In return they would be allowed to leave safely. In addition, Ranakee demanded that the data be delivered by a 'Demon' and the highest-ranking Human Officer. Marco and the others were fully aware that the Destroyer would most likely obliterate the 'Day' the moment they had what they wanted, and the decision was made to try and take out the ship by delivering a HAVOK tac-nuke in a sacrificial mission. Marco offered to carry out the task himself, but was ordered to stand down by Fenn. As Sigma Team's leader, he would sacrifice himself to save the lives of thousands aboard the ship. Accompanied by Lieutenant Martin Keel, Fenn departed for the Destroyer and detonated the nuke, obliterating the ship and giving the Frigate a chance to escape. 
While the Covenant ships were destroyed and the surviving forces scattered, Harpa marked a major loss for Humanity. The loss of Mack Senior, one of the UNSC's most capable commanders, alongside two Spartans was a heavy price to play. Marco and the surviving members of Sigma Team were to undergo psychiatric evaluations following the battle; years of war and death were beginning to take a toll on the usually stoic SPARTAN-II's. Marco confessed to Kane-098 that the deaths of his friends had disturbed him greatly, though he resolved to continue fighting the war as long as he had to. Now down to only five members, Sigma Team was deployed to Reach to begin testing new MJOLNIR armour variants until new deployment orders arrived. 
===Battle of Dorvyesk III===
Still reeling from the loss of both Fenn and Nef, as well as Richard Mack Senior several months before, the five Spartans were then sent to Dorvyesk III, a world of little significance aside from its large populace. On arrival, Sigma Team were ordered to cover the civilian evacuation there, holding the line at any cost. The UNSC were already losing the battle by the time Sigma arrived, though the Spartans were able to do massive damage to their opponents on the battlefield, an entire Covenant armour division falling to a well-placed trap by the Spartans. Nonetheless, they continued their relentless assault on the colony, slaughtering thousands in their path.
Pushed back, Sigma Team regrouped with a number of surviving marines as they struggled to evacuate the remaining civilians from the planet. Even with the SPARTAN-II assistance, they were still vastly outnumbered, many abandoning their posts to get to the remaining evac ships. Marco and Wulf became separated from the others and were trapped in a ruined building, which was soon surrounded by vengeful Sangheili. Knowing that they would not survive long if they met their foe head-on, Marco contacted a nearby Frigate, which had entered the atmosphere in order to provide air support and evacuation within the city. Giving them his exact coordinates, he called for an immediate airstrike on their location. The two Spartans took cover in the house's basement as three struck the nearby area, totally destroying the area around it. The pair were able to crawl out of the rubble, protected by their armour locking down and greatly increasing the energy shielding.
A little worse for wear, Marco and Wulf managed to make their way back to the others as the final wave of ships came in. Together, the Spartans held the line as the last few groups of civilians made their way aboard, pursued by waves of Covenant infantry. During the carnage, Resk-063 noticed a Banshee launching a fuel rod towards a fleeing family, and immediately threw himself in its path. Marco and Jax watched their friend die instantly before their very eyes, and began to make a bloody counter-attack. The usually amiable Jax flew into a rage and massacred dozens of troops before recovering the body of his best friend. With Marco, Kane and Wulf covering him, the remnants of Sigma Team made it into a Pelican dropship, leaving Dorvyesk III hours before its glassing. The loss of another comrade hit Marco hard, especially since Resk died saving a family of civilians rather than sacrificing himself to inflict massive amounts of damage on the enemy as Fenn, Nef, Jacob and Amy had. While forbade making any SPARTAN-II death public, Resk-063's comrades buried him personally back on Earth in late July, not far from the SIGMA compound in which they had grown up together.
===Fall of Reach===
Main Article: 
In early August, Marco was recalled to Reach with the rest of Sigma Team. After arriving, the Spartans were briefed on a shocking situation: the Covenant had arrived on Reach. As the had been declared planet-wide, their presence was required to help intercept and destroy all Covenant forces on the ground before they could begin their invasion in earnest and endanger major military bases and population centres. Several days later, Sigma were deployed to assist the SPARTAN-III Tau Team, who had been conducting reconnaissance in a remote region of the planet's Viery Territory. They arrived to find Tau trapped within a communications array, and enjoyed a happy reunion with the younger Spartans after driving off a sizeable Covenant attack force.
On Kane's orders, Marco and Wulf pursued a fleeing group of Covenant troops into a nearby valley, where they found evidence of a recently-established military camp, which they reported back to their superiors. That night, Marco and several other Spartans conducted a long-range recon mission into enemy-held territory, eventually confirming the location of a much larger Covenant force than expected. With a massive enemy army ready to strike across the Covenant, the UNSC quickly assembled its own force for a counter-attack the following day. With the ultimate objective of denying the Covenant a foothold on Reach, this force included several Spartan units, including Sigma, Tau Upsilon Team, and - to Marco's surprise - Tango Six, whom Sigma had not seen since the Battle of Draco III. With a lot of ground to cover, the Spartans were spread out across a wide area to support Army units and bring down any established Covenant structures in a frontal assault against their main encampment.
On the morning of August 12th the attack was launched, with Sigma joining a mechanised battalion in destroying Covenant armour raining plasma mortar fire on the main attack force. The assault was successful, and with the destruction of Covenant AA guns on the nearby mountainside air support from UNSC Frigates Grafton and Saratoga made short work of several Scarabs that were decimating friendly ground troops. Sigma eventually linked up with Upsilon Team, who had engaged enemy infantry within an abandoned miling facility. The ten Spartans butchered their way across the battlefield until they found UNSC forces engaged in a pitched battle with Covenant troops close to a large . As they debated on the best plan of attack, reinforcements led by Kryss-216 arrived to support the Spartans and provide them with transport.
The Pelicans gave the Spartans a short ride over the bulk of enemy armour before the electromagnetic fields surrounding the Spire shorted them out, leading to them crash land in the hills not far from the base of the Spire. None of the Spartans were injured due to their MJOLNIR armour, though several ODST's in Tango six were badly injured. Leaving Sal-A142 and Dorian-A188 of Upsilon Team to protect them, Marco and the others set out downhill, engaging enemy infantry as they went. The Spire itself was heavily defended, with Shade turrets and Revenants making it difficult to get close. While Upsilon Team and the ODST's drew the bulk of enemy fire Marco, Kane, Jax and Kryss would infiltrate the Spire, Wulf-041 planting a large amount of C-12 charges along key structural points as they did so.
Marco and the others were eventually able to access the Spire's gravity lift, assaulting the upper level and wiping out the defenders there. The Spartans then placed their charges, only to discover that the electromagnetic energy generated by the Spire's shield would not allow a remote detonation. At this time, the UNSC Grafton had just used it's MAC gun to destroy not far away, and was subsequently obliterated by the , a Covenant Supercarrier that had been cloaked above the battlefield. With this new threat, the Spartans had to evacuate the area quickly. Kryss was able to find a button that deactivated the Spire's shields, allowing for several Falcons to come in for a pickup. Sigma, Upsilon and Tango Six were able to escape the area, detonating their charges and destroying Spire Three as they did so. Though the battle was considered a victory for the UNSC on the ground, the appearance of a Supercarrier gave the Covenant a distinct tactical advantage, forcing a full retreat from the area. On August 17th, 2552, three days after the relative success of , which destroyed the Supercarrier, The UNSC initiated a follow-up mission, codenamed: Operation: DROPKICK. The goal of the mission was to destroy two Covenant cruisers in orbit, to cover the evacuation ships from Manassas as they fled the Epsilon Eridani system. Because of the importance of the mission, Sigma and Tau teams were chosen to lead the boarding action.
Utilising half a dozen YSS-1000 Sabre fighters that had not been used in Operation:UPPERCUT and a few Pelican dropships, Sigma accompanied Tau in assaulting one of the cruisers, assisted by several frigates and a wing of Longsword fighters. Marco, Kane and Jax were dropped into the first cruiser after concentrated MAC fire gave them an opening, followed by a platoon of EVA-capable marines. The team were able to plant a HAVOK tactical nuke in the hangar of the ship, setting it on a timer before getting to their evac pelican and escaping to assist Tau and Wulf.
Marco and Jax moved in to extract the second strike team from the hangar of the second cruiser, in which the Spartans were fighting a difficult battle against a number of Sangheili veterans in their attempt to storm the bridge. While attempting to plant the nuclear device in the rear of the ship, both Frank-A103 and Dom-A178 were killed in an ambush by an Elite Ranger team, leaving Louie-A199 to set the timer. Marco and Jax arrived in time to save the SPARTAN-III, fighting their way back to the hangar and escaping in the remaining Pelican and Sabres. DROPKICK was a success that saved thousands of lives on the planet below, but came at the price of two Spartans.
Not long after, Marco and Sigma fought in the , covering the spaceport during the initial evacuation from Covenant infantry. Sigma was joined by Upsilon and Tau once more in a bid to push back the Covenant, who were gaining ground across the city. With fourteen Spartans in combat, the enemy was massacred in the lower city streets while the evacuation effort in some areas continued unhindered. After several hours of urban warfare, the Spartans were given direct orders from HIGHCOM to travel to an ONI facility on the far side of New Alexandria, where it was revealed that Doctor Calvin Roe, the progenitor of the Sigma project, was holed up with an ODST team defending him. Though vocally unenthusiastic about their mission, Marco went along with the others in falcons to cover Roe's Pelican. When they reached the building, they found it under attack by dozens of Covenant soldiers who had almost broken through to the Doctor's saferoom. Wulf-041, Dan-A105, Chris-A189 and Eugene-A133 landed, and began clearing out the building, cutting a bloody swathe through the enemy until they reached Roe and his bodyguards. The Doctor, worried about enemy forces accessing the building's databanks, dispatched the Spartans to clear the level below and destroy the main servers, which had not been wiped clean of data pertaining to Earth and other colonies. Wulf led the others to the lower level to clear it out while Roe and his guards made their way to his personal pelican.
Immediately after taking off, Roe announced that he had been given explicit orders by ONI to demolish the building, and activated the charges on a timer with the Spartans still on the building's sub-level. The Doctor ignored Marco's requests to stop the timer and allow the Spartans to escape, instead flying away from the city. Though Wulf and the SPARTAN-III's attempted to make their way outside, there was no possibility of them making it in time. Before they could reach the landing pad, the entire ONI building detonated, killing the four of them instantly. This shocked the remaining Spartans, who were still in Falcons nearby. Marco immediately piloted his Falcon after Roe's Pelican, stating his intent to kill his old enemy.
Marco was serious in his intent to kill Roe and opened fire on his Pelican as they caught up in spite of orders from Kane-098 to stop. Another Falcon, piloted by Martin-A136, assisted Marco, the pilot having lost three of his best friends because of Roe's disregard for human life. After a lengthy chase, spanning several hundred miles, Roe's Pelican finally landed at Outpost Foxtrot Whiskey, a remote military base on Reach and rally point for local UNSC forces. Upon arrival, Roe had the outpost's anti-air guns target the incoming Pelicans as hostile targets, forcing the Spartans to land immediately before the Marines on-site realised what was going on and shut them down. While Marco's dropship landed safely, a Pelican piloted by Sal-A142 was shot down just outside the base.
The moment his Falcon touched down, Marco leapt out and ran for the base after Roe while the other Spartans made their way to the crash site. Though the passengers - Kane, Jax and Jordan-A111 - were unhurt, Sal had been fatally wounded and died shortly after her body was dragged from the wreckage. Entering the outpost, Marco snatched a shotgun from the hands of one of Roe's ODST bodyguards and went after the scientist, who had fled into the base and was looking for a way to contact Reach HIGHCOM. He eventually forced his way into the office Roe had sealed himself in and confronted the man responsible for turning him into a Spartan. Overcome with grief and rage over the pointless deaths of so many Spartans, he ignored Roe's attempts at reasoning with him and executed the doctor, leaving his body behind before returning to his comrades. Though utterly shocked at what Marco had done, neither Kane nor Jax reprimanded him for his actions and instead chose to cover for Marco.
As Marco came to his senses, he became dejected over killing Roe in such a manner and offered to turn himself in. To his surprise, Kane contacted Reach HIGHCOM with news of Roe's death, though he informed them that his Pelican had instead been shot down as he attempted to escape New Alexandria. They were then informed that a sizeable Covenant attack force was en-route to the base after wiping out a nearby UNSC garrison, and that reinforcements would not be available until the following morning at the earliest. With little time to prepare, Kane took charge and had Marco and some of the SPARTAN-III's head into the nearby foothills to set up traps for the advancing Covenant while he and the few still stationed at Foxtrot-Whiskey manned the walls and recalibrated its automatic defences.
Rallying the retreating UNSC forces around the mountainside base, the Spartans set up remote turrets and an array of mines. When the Covenant did arrive, Marco took a platoon of marines and engaged the enemy in the foothills around the base of the mountain, while Jax-007 took a small vehicle contingent in to draw away the bulk of enemy armour. Marco's forces, assisted by Dorian-A188, Jordan-A111 and Nelson-A122, took down dozens of enemies in fierce close quarters combat, leading Covenant troops into ambushes and making use of their elevated position to gain the upper hand during the battle Jax's group fared just as well, their warthogs being pursued by wraiths into a narrow valley where the cumbersome tanks could be easily flanked and destroyed by other Spartans. 
In spite of their initial victories, however, the sheer number of Covenant soldiers, as it had done many times in the past, allowed them to simply keep attacking until they overwhelmed the human defenders. After contacting HIGHCOM once more, Kane requested a bombing run just outside of the outpost on the tightly-packed Covenant forces. Surprisingly, it was accepted, Shortsword bombers decimating enemy attackers outside of the base. As Marco received the order to retreat, he noticed Dorian-A188 of Upsilon Team fighting a number of Sangheili at once. Before the SPARTAN-II could reach him an Officer stabbed Dorian through the chest with an energy sword, killing him instantly. This sent Marco into a furious rampage, gunning down the trio of Sangheili before taking the sword and butchered dozens of foes, causing many others to flee in terror. Marco recovered Dorian's body and returned it to the base, covered in alien blood. 
As an attack by Shortsword bombers momentarily halted the Covenant advance, Marco and the others fled back into the outpost to regroup. After raiding the remains of Foxtrot-Whiskey's armoury for weapons, Marco discovered a single FENRIS nuclear warhead that had been left behind. Unable to take the bodies of their fallen comrades with them, they linked the warhead to Sal and Dorian's MJOLNIR suits and set up a timer for the survivors to flee the base. Taking several Pelicans, the Spartans and surviving ODST's left Outpost Foxtrot-Whiskey before Covenant reinforcements could reach it and vaporised the entire area.
Sigma Team would arrive at several days later, parting with the surviving troopers as they contacted their superiors for orders. Upon reporting the status of their MJOLNIR suits, Marco, Jax and Kane were given special access to several newly-developed prototypes being held in the base. While not fully tested and calibrated, Sigma took the armour and spent some time getting used to it before setting out once more to engage enemy landing parties. Marco and the others would spend several days operating far away from friendly forces and cut a bloody swathe through Covenant patrols before losing all contact with HIGHCOM. From what they could garner from scattered UNSC transmissions across Reach, the planet had more or less fallen to the Covenant's onslaught and evacuation points were quickly dwindling.
With no choice but to flee Reach, Marco and the surviving Spartans attempted to reach the , which was docked in the Asźod ship breaking yards, before it left the planet. This plan would ultimately be shattered when the ship departed not long before their arrival in Asźod, leaving the Spartans stranded with no slipspace-capable transport. After discussing their potential options, Marco being in favour of taking down as many Covenant as they could before they were overwhelmed, they picked up a distress signal from the UNSC Bright New Day. Recognising the ship, which had been scheduled for decommissioning when Reach was attacked, they contacted those aboard and found that Richard Mack Jr. and the remnants of Whiskey-04 had been attempting to use it to escape Reach before coming under attack. Discovering that its skeleton crew could get the ship off the ground and into orbit, the Spartans raced to defend it.
While Marco assisted Whiskey, Jax, Alex-A121, Nelson-A122 and Jordan-A111 offered to draw enemy attention in the shipyards while the other Spartans handled takeoff. Having seen half a dozen Spartans die in the last week, Marco was reluctant to see his longtime friend stay behind, but ended up going with Kane and the others to the ship. Using flares and insults over open radio channels, Jax was able to attract a surprising amount of enemy attention, having mocked Covenant beliefs to provoke them. The four Spartans held their own for a short while, though it became clear that they wouldn't last long. Jordan was killed while taking most of a building full of foes with him, while Nelson sustained severe injuries and could not retreat to their location. As the Bright New Day took off, moving over the shipyards, Alex and Jax hijacked a pair of banshees, managing to fly into the ship's hangar while Marco and the others provided covering fire with the ship's guns before it reached orbit. Much to Marco's chagrin, they did not attempt to rescue Nelson. The Day left Reach and managed to narrowly evade the Covenant fleet, most of which was occupied with pursuing the Pillar of Autumn or glassing the planet. 
Using the ship's navigational computer, the Spartans plotted several slipspace jumps to randomised locations in accordance with the Cole Protocol, quickly leaving the Epsilon Eridani System. With only a fraction of the normal crew needed to man a ship, Sigma Team took over as many roles as they could with Kane in charge. Marco would look back on the Fall of Reach as one of the darkest times in his life, mourning Wulf and the SPARTAN-III's. Though Kane and Jax would never bring the topic up to him again, he privately regretted murdering Calvin Roe and - to his own surprise - realised that for all the mistreatment towards him and the other members of SIGMA, Marco could not bring himself to truly despise him.
===Loss of Hope===
Main Article: Loss of Hope
After making two Slipspace jumps, the UNSC Bright New Day received a distress signal emanating from the colony world HopeLosing Hope, posts 216, 232, 242, 251, 256 and 260. MCPO Kane-098, as the senior-ranked person on the ship, ordered the crew to investigate the planet. Upon arrival, they discovered that the planet was under attack, and after managing to cripple a Covenant ship, were forced to land due to plasma torpedo damage rendering their FTL drive inert. They were lucky not to have been killed. Leaving Whiskey-04 in command of the ship, the three SPARTAN-II's and three SPARTAN-III's of Sigma Team set out for the nearest city, Port Neandra, in search of a slipspace drive or friendly UNSC forces. Upon entering the city and finding it not only deserted, but with all electronics fried as a large EMP had detonated in the area. While Jax-007 attempted to activate a data terminal, the team ambushed a large Covenant patrol, taking down several Wraiths and Phantoms along with a Brute Chieftain.
Jax was able to find a city map, which led them to a large underground facility in the city, where three partially dismantled UNSC Frigates sat. As they approached, one of the frigates was destroyed by brutes, and the Spartans were forced into an engagement with several more Covenant squads who had been lying in wait. Kane-098 set up a defensive position covering the others with his Sniper rifle while Marco led Louie-A199 and Martin-A136 in a counterattack, opening a large roof access hatch for extraction, while Alex-A121 and Jax-007 went in search of a working FTL Drive.
After eliminating their Covenant attackers, the six Spartans secured the undamaged FTL drive and waited for Pelican evac supplied by Sergeant Major Richard Mack Junior. Marco helped attach the drive to the dropship before it took off. As they left Port Neandra, the ground beneath them began to shake as tremors rocked the entire planet. The Covenant would continue their pursuit, sending a wave of banshee fliers after them. Fearing that their new slipspace drive would be damaged, Marco leapt from the dropship and hijacked a nearby Banshee, using it to harass and destroy most of their pursuers before catching up with Sigma and Whiskey-04 in the Bright New Days hangar. The newly acquired Slipspace drive was installed by technicians as the frigate left Hope and prepared to escape the system, but Kane-098 ordered the ship to stay in spite of protests from Marco and Alex. Due to the unusual tectonic activity across Hope's surface, Sigma would remain and watched as the planet eventually imploded. 
===Battle of the Zenith Complex=== 
Main Article: Battle of the Zenith Complex
Shocked at the planet's sudden destruction, Marco once again suggested that Sigma leave the system. His request was denied, as Kane wished for them to recuperate and assess the situation in case they could make contact with the distant UNSC forces already fighting over a newly-discovered worldGaining Faith, posts 11, 30, 60, 79, 88, 95, 107, 115, 124 and 136. The Spartans rested for a short amount of time, making checks on their MJOLNIR armour. Suddenly, a small prowler exited slipspace not far from the Day, apparently having lost all power. Marco, along with Kane-098 and Jax-007, took a pelican to investigate the ship, managing to enter it through an airlock. After several minutes, the Spartans ran into the last person they expected: Elena-071. This discovery shocked Marco to his core, having grieved over his best friend's supposed death for over twenty years before this chance meeting.
After reuniting briefly with their fellow SPARTAN-II, the ship was reactivated. Elena then revealed that she was on a top secret mission from ONI, codenamed Operation: ASPHALT. While the Day underwent more repairs, she would recruit Sigma Team for a sudden mission to the strange planet's surface. Following the slipspace trail of allied UNSC ships, the Heavens Asunder jumped, arriving above the new world. While onboard, Elena, who was wearing a field prototype of the MJOLNIR Mark VI armour, gave the others some upgrades to their well-used suits. Kane-098 received a thermal vision mode for his HUD, Jax-007 installed force-multiplying circuits that improved his reaction time, and Marco gained a shield-overcharging module for his armour.
Taking Elena's Pelican to the alien planet, Sigma was attacked shortly after landing by an unknown enemy; with high-powered energy weapons. After a short pursuit through the surrounding forest, during which Marco was able to destroy two of the machines, the Spartans regrouped, discovering a structure atop a ridge not far from their location. Still being chased by 'Sentinels', Sigma Team made it into the structure, where they discovered a holographic control panel. Elena, despite being cautioned, began to press the buttons without knowing what they could do. One such button activated a teleporter a short way from the facility, whereupon Covenant forces, who had been located at another terminal elsewhere on the planet, began to pour through, nearly overwhelming Jax-007 and assaulting the structure. Another button opened up a concealed tunnel, leading into the mountainside.
Marco was sent back to the dropship while the others held off the massing Covenant forces to activate the long range communicator in order to get in touch with the Day, and call for SPARTAN-III reinforcements. After several attempts, Marco was able to contact Sergeant Major Mack who followed the Heavens Asunder's slipspace trail after repairs were finished. A dropship was dispatched carrying Martin-A136, Louie-A199 and Alex-A121 to the planet. Returning to the structure with the SPARTAN-III's, Marco found it overrun with Covenant forces. Lying in wait, the four ambushed an Unggoy patrol, killing all but one member. Marco would tie the hapless alien to a Ghost wired with explosives before sending it flying up a forest slope until it crashed into a fortified enemy position.
Marco and the younger Spartans then commandeered several Ghosts and launched an assault on what remained of the Covenant fortifications atop the ridge as enemy reinforcements arrived. Marco directed the others down the ridge, a high-speed chase ensuing as both Covenant and Sentinels began to battle around the structure. Kane then detonated a number of C-12 charges from within the Forerunner structure, creating a massive eruption that forced the Spartans to abandon their vehicles and move forwards on foot. Momentarily cut off from his comrades, Marco was assaulted by two Hunters. Dodging several blows, Marco was hit squarely in the chest by a Hunter's fuel rod cannon, saved only by his new shielding upgrade. Thrown to the ground, the SPARTAN-II was saved when Louie-A199 rammed one Hunter and cut in in half as Martin finished the other off.
After making their way to the rendezvous point at the base of the ridge, the four Spartans met up with Elena-071, who managed to decapitate a Sangheili with a well-aimed kick as she reunited with Marco. Martin, Alex and Louie were introduced to the Commander, and after sending a message to the Day for extraction, the seven Spartans bunkered down in anticipation of a Covenant and Sentinel counter attack. As enemy forces approached, Louie-A199 and Alex-A121 set up their remaining C12 charges at the base of the hill, assisted by Marco. They then fell back to the summit as a large Covanant force emerged from the forest, led by several Revenants. On Kane's order, they detonated the explosives, disrupting the Covenant advance and leaving the survivors as easy pickings for rifle fire.
Shortly after, Sigma Team were evacuated on a Pelican dropship, piloted by Richard Mack Jr. As they escaped the conflict, Elena ordered Mack to divert his course to her own modified dropship, which was being investigated by a Covenant patrol. When they got close enough, Elena leapt from the Pelican's open doors, closely followed by Marco, ambushing and wiping out enemy forces before getting aboard. The two pelicans then took off from the planet, heading back to the Bright New Day and Heavens Asunder. Marco and Elena went back to the prowler, where they spoke for some time before the other Spartans attached a docking tube to the ship to come aboard. As the airlock opened, Elena grabbed Marco and threw him in before sealing the door. She apologised, stating that ONI had ordered her to return alone, and that the others were not supposed to even know that she was alive. Detaching her ship from the frigate, Elena made a slipspace jump to an unknown area of space. Though the other Spartans wished to follow her, Marco explained that she would not have abandoned them without good reason, still trusting his old friend after all these years. The crew of the Bright New Day then calculated another random slipspace jump to throw off any Covenant forces, and left the system.
===Battle of Second Sanctum===
Main Article: Battle of Second Sanctum
Shortly after their escape from the Zenith Complex, the Bright New Day picked up a transmission from a UNSC beacon near one of many designated fallback points for the Navy. While Marco suggested that it might be a Covenant trap, Kane gave the order to investigate the site, where they could possibly link up with friendly forces and assess the situation before returning to Earth. Travelling to the source of the beacon, they discovered a small group of warships: Battle Group Cossack. After establishing communications with the group, the Spartans met with Captain Jeanette Nisha aboard her , the UNSC Theseus. Marco was surprised to find that she was an ONI officer, and still fearing reprisal for his killing of Doctor Roe on Reach, let Kane do most of the talking. As it turned out, Battle Group Cossack had been assigned a dangerous mission by HIGHCOM that involved infiltrating a heavily-guarded Covenant fortress known as Second Sanctum to free Human POW's and destroy the base. While sceptical of how they would achieve this with very few ships and barely two hundred combat-ready personnel available, Sigma Team had no choice but to obey Captain Nisha's orders and joined up with the infiltration team in preparation for the operation. 
While Jax, Louie and Alex would join a group of elite members in sneaking into the base aboard a stolen , using Unggoy prisoners for assistance, Marco and the rest of Sigma would help to lead the main attack force once the infiltration team began their own assault. Before the operation Marco confided in Kane that this would likely be a suicide mission, and while his team leader agreed with his assessment he made it clear that defeat was simply not an option at this point and that they had to return to Earth alive at all costs. For Marco, the fact that Elena was still alive was more than enough motivation for him to survive what would surely be a costly operation. Several hours after the infiltration team's Lich departed for Second Sanctum, Captain Nisha ordered the Battle Group to follow it through slipspace and prepare for combat. Sure enough, they were thrust into battle almost immediately after arriving in-system, engaging a pair of over the moon with minimal losses before Marco and the others were dispatched via Pelican to attack Second Sanctum itself.
The descent towards the Covenant-held moon was not easy, with Kane piloting their Pelican through heavy anti-aircraft fire as they looked for a safe spot to land. As they neared Second Sanctum, one of their wings was incinerated by a plasma mortar, forcing the Spartans to make a hard landing in the forests surrounding the fortress. Marco, Kane and Martin were none the worse for wear after this, and swiftly engaged an incoming Covenant infantry force before making their way up towards one of Second Sanctum's loading bays to regroup with Jax and the other Spartans. With no time to lose, Kane ordered the SPARTAN-III's to begin destroying the enemy network of AA guns while they searched for civilian POW's deeper into the fortress. With friendly forces keeping a Covenant Legion bogged down in heavy fire across the forest and nearby beaches, Sigma was able to blow through several security checkpoints with ease. Marco was soon forced to take up Covenant weaponry after ammo ran low, and led the charge with a pair of stolen plasma rifles as they neared the facility's cell blocks. 
Hearing the approach of a group of Hunters, Jax had Marco board a Wraith tank in a nearby vehicle bay and ambush the powerful aliens while he acted as bait. After waiting for them to pursue his comrade out into the open, the Spartan incinerate them with close-range plasma mortar fire and utterly annihilated several more squads of approaching enemy troops while Kane and Jax entered the prison area. He continued to hold off Covenant reinforcements as they rescued dozens of captured civilians, though his Wraith was soon badly-damaged by sustained plasma hits and anti-tank weaponry soon shut down but its powerful mortar. He would eventually abandon the vehicle and joined the others in escorting the civilians back out towards a landing zone where the infiltration team's stolen Lich was situated. While they initially sought to use it to evacuate all the civilians offworld, it had been attacked by Covenant troops and has suffered a hull breach despite the best efforts of the ONI Security personnel defending it. Leaving the civilians there while Kane called for more transport Pelicans, the Spartans led another assault on the beaches to draw attention away from the others and prevent the bulk of Covenant troops from regrouping. Marco was the first to leap into combat as they hit a group of Sangheili snipers from behind, slaying numerous foes and using their own weapons to pin down advancing infantry lances. When news arrived from the SPARTAN-III's that they had slain a Sangheili Field Master assumed to be the commander of local Covenant forces, what had once been a suicide mission was looking very much like a victory from Marco's perspective.
This feeling would be very short-lived, however, as a much larger Covenant fleet arrived in-system and decimated the UNSC attack force in orbit. What remained of their ships fled around the other side of the moon, depriving their groundside troops of valuable air support while thousands of fresh Covenant troops landed outside the fortress. Marco and Alex-A121 would lead a counter-attack to defend their position within Second Sanctum, but were slowly repulsed through sheer numbers and the loss of most of Papa Company and their militia allies. They were eventually forced to retreat back towards their landing zone, sealing as many doors behind them to hold off a particularly vicious Sangheili attack force. After regrouping with as many of their forces as possible, Marco and the other Spartans boarded their now-damaged Lich and moved to rescue Louie-A199 and a friendly platoon from hostile reinforcements. While they did attempt to save Commander Erwin Durant and his men, the officer ordered the Spartans to flee shortly before his position was overwhelmed by Covenant special forces. As their Lich moved away from Second Sanctum, it was struck repeatedly by enemy anti-air fire and was forced to crash-land in a remote area to the north.
While the Spartans and their passengers all survived, there was nothing more they could do on the ground. As such, they radioed for immediate extraction, hoping that they had some air support remaining. Marco was happy to find that the UNSC Bright New Day had survived and dispatched several Pelicans to airlift them to safely. Using the remnants of the 9th Tactical Fighter Wing as cover, the dropships soon got them away from Second Sanctum and back aboard their Frigate. Once there, they plotted an immediate course out of the system while Captain Nisha, who revealed that the operation had been wholly her idea and not an officially-sanctioned mission, remained behind to sacrifice her ship to distract the Covenant and destroy Second Sanctum with nuclear missiles. While initially enraged that the ONI officer had gotten so many killed, Marco respected her decision and watched as the UNSC Theseus goaded the Covenant fleet into attacking it before launching a suicidal attack with everything it had. Shortly after confirming that Second Sanctum had indeed been obliterated, the Bright New Day and a Destroyer, the UNSC Illustrious, made the jump to slipspace. 
In the aftermath of the costly battle, Marco helped oversee the transportation of the wounded over to the Illustrious; the Day was to remain in the hands of Sigma Team and Whiskey-04 upon Kane's insistence that they were on a secret mission. While aware that his teammate - like Nisha - was lying about their true intent of simply getting back to Earth, he kept quiet, since their vessel was poorly-equipped to handle the amount of soldiers and civilians currently aboard the Destroyer. After trading some supplies, the Frigate and its passengers continued their slow journey back towards Earth.
===Battle for Moscow===
Main Article: Battle for Moscow
After a long journey, the Bright New Day arrived in the Sol system to find it under attack by the Prophet of Truth's . After making contact with UNSC forces, they began making their way towards Earth and were soon detected by Covenant ships in orbit. As they drew closer, Kane ordered all of the Spartans and ODST's to the ship's , and plotted it on a collision course with a nearby CCS-class battlecruiser in he Earth's atmosphere. Barely a minute before the Frigate collided, Sigma and Whiskey launched their pods, heading straight for Earth. The remaining crew and technicians on the Day were able to evacuate in the few remaining lifeboats and Pelican dropships. The team landed near Moscow, Russia. Marco found Sergeant Major Mack, along with Jax-007 and Privates Raikov and Peterson, who informed him that two other ODST's had been killed in the drop. Kane-098, Martin-A136 and Corporal Bell were next to arrive at their rendezvous point on the city's outskirts, meeting up in an abandoned schoolhouse. While they discussed their potential options, Marco suggesting that they contact HIGHCOM, two enemy corvettes dropped in and began their assault on Moscow. With no other choice, the Spartans and their allies moved to defend the city alongside local Marine forces and split up into several teams.
Marco's team moved towards the city centre, contacting the local police forces with the help of the Russian-speaking ODST Raikov and planning a counter-attack against the invaders by setting up explosive traps and sniping points across streets by the enemy landing zones. Just as it seemed they would halt advance of enemy infantry, over a dozen Wraith tanks moved in, overwhelming their meagre defences and driving Sigma back. The Spartans, along with the ODST's and Marines, were forced to pull back into a plaza in an attempt to trap the tanks in the narrow streets surrounding it. Marco, Jax and Whiskey-04 set up a defensive position inside a ruined building while Alex and Louie acted as spotters, waiting for the column of wraiths to arrive.
Eventually, the attack came. Louie-A199 and Alex-A121 unleashed several rockets on the first Wraiths, destroying them, and then fell back towards the main building. Marco and Jax provided covering fire from the advancing Covenant infantry with mounted machine guns. As the battle raged on, things were going badly for Whiskey-04. Marco, who had spent most of the battle operating a machine gun, was forced into a hasty retreat along with the surviving UNSC forces, though they had bought the local Marines all the time they needed to flee. 
Several evac Pelicans met Marco and the others half a mile north and extracted them from the combat zone. As they left, the Marine NCO detonated a HAVOK nuke left within Moscow, destroying all Covenant forces in the area and downing their remaining ship at the hefty cost of over a third of the ancient city. While even Marco considered it a heavy price to pay for victory, stopping the Covenant at any cost had become the priority. The Spartans returned to the UNSC's PILLAR Base, situated under Mount Everest. Mack Junior was reassigned almost immediately after saying his goodbyes to Marco and the Spartans, who had their injuries and armour checked out. To replace their heavily-damaged and failing Mark V suits, Sigma were given the new MJOLNIR Mark VI armour, which would come in useful for the heavy fighting they would soon see.
===Battle of Sector Six===
Main Article: 
On November 17th Sigma was deployed once again, this time without their SPARTAN-III comrades. They were sent to an area east of Pawa on the Afganistan/Pakistan border with a mission was to calculate the landing site of the incoming , who was en-route to Earth. While Marco and the others had never met him, even they had heard of the legendary Spartan's feats and gladly took part in the operation. Deploying with a group of Orbital Drop Shock Troopers, Marco, Kane and Jax moved in, assisting local Marines in pushing back against a large Jiralhanae-led force trying to hunt down pockets of human resistance in the area. Provided with a by his superiors to pinpoint SPARTAN-117's position, Marco and the rest of Sigma were forced to fight through several miles of rough urban terrain, facing serious opposition the whole way doing everything they could to impede the Covenant's advance. 
Despite their best efforts to complete the mission, Sigma Team had not anticipated the sheer number of enemy forces, and Marco was soon forced to reunite with his comrades. Knowing that they would likely be overwhelmed before they could complete their mission, Kane ordered Marco to hide the designator in the ruins while the Spartans continued to run interference, drawing as much attention as possible towards themselves. Radioing for to carry out the rest of their mission with the laser designator, Marco and Sigma led the rest of their force in a counterattack, destroying several Wraith tanks in the process. While friendly forces in the area took heavy casualties in the subsequent battle, one of the troopers was able to successfully pinpoint SPARTAN-117's landing site in Africa and the order was given for local UNSC forces to withdraw.
Upon hearing of the mission's success, Sigma Team fell back, moving into a nearby bunker network where they met up with the surviving troopers and Marines. While eager to participate in a subsequent mission to recover SPARTAN-117, the Spartans were delayed by a sustained bombardment by Covenant forces in the area that left them unable to leave their shelter for close to half a day. Eventually rescue arrived in the form of a Pelican airlift, and while the exhausted Marines were taken to the nearest military base to recuperate Marco's team were immediately taken towards , where a desperate battle was being fought against the hub of the invading Covenant forces.
===Battle of Voi===
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Sigma Team would arrive late in the day, far behind the primary assault force that had been cutting a path through the Covenant's perimeter defence around a massive . As they approached what remained of the city, Sigma's Pelican dropship came under heavy anti-aircraft fire, and was forced to land after sustaining cannon fire that destroyed one of its thrusters. After ensuring that the crew were okay, Marco and the others set out on foot, making short work of several enemy patrols as they neared the edges of the excavation site, which they recognised as Forerunner in origin. Intent on making their way to the at its centre, Sigma Team was stopped only by the timely arrival of , which launched a direct assault on the Forerunner vessel. 
The Spartans watched from afar as this attack proved to be entirely ineffective, unable to do anything as a slipspace portal of unprecedented size opened above the site and allowed what remained of the Covenant fleet through it. With the battle seemingly won, Marco and the others attempted to contact their superiors for further orders, only to be interrupted by the sudden arrival of a heavily-damaged battlecruiser emerged from slipspace in the skies above and crashed on the city's outskirts. In the confused minutes that followed, an entirely new enemy emerged and began to infest the city: the .
Marco, like his fellows, was horrified by the Flood. Having not been briefed on the virulent parasite before, Sigma Team began a fighting retreat out of Voi, harried by the possessed corpses of friends and foes alike. The Spartans quickly ran low on ammo and were forced to scavenge enemy weapons to fend off the seemingly endless tide of walking corpses, with Marco reduced to fighting hand-to-hand against the relentless monstrosities. Hard-pressed and fighting for his life, Marco found his strength waning when Sigma Team were heralded over an open COM not by UNSC reinforcements, but by who had just arrived over Voi. A barrage of plasma fire cut through the Flood forms bearing down on the Spartans, who were greeted by a cadre of heavily-armed and surprisingly friendly Sangheili warriors.
While Marco still harboured a serious grudge against the Sangheili after decades of fighting and killing their kind, he obeyed when ordered by Kane to stand down and work with the Sangheili, whose energy weapons helped turn the tide in their favour against the Flood. Fighting side by side with their former enemies, Sigma Team managed to push past the Flood and reached Voi's outskirts, where a staging post had been set up by surviving UNSC troops to hold back the infected and airlift survivors out of the city. Marco parted way with the Sangheili on pleasant terms, appreciating their viciousness and bravery in what had been one of his more gruelling battles. Sigma Team were picked up shortly after, and transported as far from the city as possible as Sangheili vessels began to glass the entire area, burning vast swathes of land in an attempt to end the Flood outbreak before it could spread further. Watching from the back of their Pelican as they escaped, Marco found himself glad to see a glassing for the first time in his life.
===Battle of PILLAR Base===
After the and several Sangheili ships departed through the Voi portal in pursuit of the Covenant's remaining leadership, Marco and Sigma Team remained on Earth. With the very real possibility of a massive Flood hive speeding towards the planet, the Spartans relocated to PILLAR base, where they were met with Fleet Admiral Lord , leader of the United Nations Space Command. Preparing for the worst, Hood had Sigma Team remain on standby, ready to act as a rapid-response force against any new invaders. Thousands of Army and Marine personnel arrived at the base shortly after from existing deployments, battered and depleted after weeks of heavy fighting around the globe. While he spoke very little to his fellow servicemen, Marco soon realised that many of his comrades believed that the human race was truly on the verge of extinction and were looking to his comrades as a source of hope in mankind's darkest hour, something that weighed heavily on his conscience as he dwelled on the battle to come. 
Close to a week passed with no news from the portal, and while an was detected close to Mars and put the remaining UNSC forces on high alert, it did not prove an issue as it vanished into slipspace almost immediately after. While relieved that he would not have to fight the Flood again following this perplexing event, Marco was soon informed that a sizeable Covenant force that had been left stranded on Earth were launching an offensive towards PILLAR base, intent on killing the high-ranking UNSC personnel still coordinating defensive efforts across the planet. Faced with an attack force numbering in the tens of thousands, backed up by a number of scarab walkers and even a damaged but heavily-armed corvette, Sigma Team found itself preparing for a potential siege. After ensuring that Lord Hood and other officers were safe in the command room deep underground, Marco and the others took to the field.
With most of their resources having already been devoted to other deployments, the Spartans were forced to make do with whatever equipment PILLAR base had left. Unwilling to fight a defensive battle that could allow the Covenant's scarabs to start boring into the mountain, Marco, Kane and Jax split up to lead three separate counteroffensives around the base. Utilising a few Warthogs and ageing anti-aircraft tanks, Marco led an assault downhill towards an armoured column, destroying several Wraiths before withdrawing. Pursued by vengeful Jiralhanae-led forces, Marco lured his foes into a minefield that made short work of several hundred attackers. 
While Sigma Team's delaying tactics inflicted horrendous casualties on the Covenant army, their own limited numbers and supplies soon put them as a disadvantage. Once the enemy began to field Scarab walkers, the UNSC's outer defences fell apart and most of Marco's own strike force was killed by focus cannon fire that wrecked most of their remaining vehicles. Now on foot, Marco continued to fight across the network of security bunkers surrounding PILLAR base, holding the line with a heavy machine gun as their foe dispatched wave after wave of Grunts in a suicide attack on the Spartan. The battle dragged on through the night, and though the Scarabs began to break through human lines a timely bombing run by a Longsword fighter wing destroyed one and crippled another, grinding things down to a fight of attrition around the base. 
By sunrise, news finally arrived of reinforcements en-route from military deployments on Luna and Mars. Sigma Team, which had rallied the base's defenders and set up a line of hastily-deployed instacrete bunkers and antipersonnel mines close to PILLAR's entrance, was soon contacted by Sergeant Major Richard Mack Junior, who had been given command of a new unit. Deploying from low orbit, several ODST platoons smashed into the Covenant's faltering lines, while a secondary attack force accompanied by Martin-A136, Alex-A121 and Louie-A199 arrived from the south. Together they launched a brutal assault, slaughtering what remained of the opposing force. In the rout that followed the enemy commander, a high-ranking Jiralhanae Chieftain, was shot dead by Kane from afar, utterly breaking any cohesion the enemy still had. By the day's end, not a Covenant single survivor was reported in the area around PILLAR base and the all-clear signal given to Hood and the other commanders.
With the Covenant force broken and any Covenant survivors now scattered across the Earth or fleeing outsystem, Marco and Sigma Team had little to do but await news from the other side of the Voi portal. Having spent almost all of their time going from one battle to another since their return from Reach, Sigma Team were officially debriefed and gave a detailed report of their actions in the past few months. Marco noted that Kane had deliberately omitted the manner of Doctor Calvin Roe's death from his report, and though he did not thank him for it knew that his comrade would look out for him at all costs. Marco took this lull in the fighting to rest and recuperate from what had felt like an endless series of battles, and was still stationed in PILLAR base when allied forces returning through the Voi Portal confirmed that the Covenant had at long last been defeated. The news spread like wildfire, and though Marco was happy to join in the celebrations could hardly believe that the war was over after spending most of his life fighting it.
===War's End===
With the Human-Covenant War finally over, Sigma Team remained active, its members among the very few surviving SPARTAN-II's after the decades-long war. The three Spartans visited the Hillside memorial in East Africa on March 3rd, 2553, shortly after the official ceremony ended. Lord Hood, grateful for the help they provided him during the battle of Earth, allowed them to pay their respects before departing. Two days after the ceremony, Marco was promoted to the rank of , though he saw it as a fairly meaningless gesture after losing so much over the years. Martin-A136, Louie-A199 and Alex-A121 were to remain with Sigma for several months until either the UNSC Navy or the Office of Naval Intelligence reassigned them. By August, the SPARTAN-III's had left the team, though they remained good friends with their older brethren.
Eight months after the end of the war, while Marco was undergoing a simple health checkup and blood test, a doctor discovered that his DNA was remarkably similar to that of a marine NCO, Gunnery Sergeant Michael Wade. Wade was called up to the UNSC Brighton, where Marco had the test. After meeting Michael, Marco questioned him repeatedly about his life and childhood, something that the Marine found very strange. After Michael revealed that he had a brother three years older than him who had died suddenly when they were kids, Marco removed his helmet and announced that he was Michael's supposedly dead brother. The Marine was shocked at this revelation, and demanded answers from Marco.
He explained to Michael that, from what he could garner, after he and the other Spartan candidates were kidnapped, they were replaced with , that quickly died. Although Wade did not at first believe the Spartan claiming to be his brother, but after much conversation and evidence, Michael finally accepted Marco, whom he had not seen for thirty-six years. While the Office of Naval Intelligence was aware of this, no action was taken against Michael or his family, though they were placed under distant observation so that the Spartan would not notice. Michael informed Marco that their parents had been killed during the Battle of Earth; two casualties among billions lost there. To his own surprise Marco was not particularly upset by this news; having spent most of his life away from his biological parents he was emotionally distant from their passing. Michael also revealed that their parents had a third child, Amanda, in 2532. While he was twenty-one years older than Amanda, Marco asked about his younger sister and wished to see her. It turned out that immediately following the War she had fallen out with Michael when she enlisted in the UNSC Marine Corps to avoid dealing with the death of their parents. Michael urged Marco to simply forget about Amanda as he was still furious at her actions.
Michael invited Marco to stay at his house, where he was home on leave with his wife, Melissa, and his two-year-old daughter, Kate. Marco accepted, and stayed there until Marco had to return to active service in the UNSC. Michael then informed Marco of his plans to retire from military service once his tour had finished to spend time with his family. Marco was happy for his brother, but deflected any questions pertaining to his own possible retirement; he knew that he would most likely belong to the military for his entire life, and that the only way he'd be leaving was in a body bag. After nearly a month of leave, he was recalled to PILLAR base in India to meet with the rest of Sigma Team before getting back to duty.
===Post-War===
Although the war was over, the Covenant had survived in the form of dozens of sub-factions that fought over parts of their former empire's space. Marco and the surviving members of Sigma were kept within the UNSC Navy while most of the remaining SPARTAN-III's were transferred to the newly-formed alongside the first SPARTAN-IV supersoldiers. While Marco saw these new soldiers as somewhat inferior compared to previous Spartan generations in terms of training and experience, he did appreciate that they were all consenting adults instead of kidnapped child soldiers like he and his peers had been. For several months after, the Spartans were tasked with hunting down any Covenant remnants that had survived the end of the war.
In early 2554, Marco would be part of the rescue team that extracted Elena-071, Kane-098 and Echo 1-1 from Schönheit in the conclusion of Operation: ASHES. There they were able to recover the preserved corpse of Hank-136, an old comrade thought long-dead. While Marco and the others wished to have Hank returned to their team, his mental instability following his resuscitation led to ONI placing him in Fireteam Thor with other troublesome Spartans. 
===Hunting down Meridus===
In August of 2554, Marco, Jax and Kane were tasked with the elimination of a Jiralhanae Chieftain named Meridus in what became known as Operation: CATFISH. Once a mid-ranking leader in the Covenant military, Meridus had become a powerful warlord following the war's end and was attempting to unite several large Jiralhanae tribes with other former Covenant forces in an attempt to kill the Sangheili leader and blame it on the UNSC. After spy probes uncovered the location of Meridus' base on a far-off colony of Sundered Heart. Once a mere outpost on the edge of Covenant space, the Covenant remnants had turned the small world into a fortress, guarded by dozens of capital ships and even a single CSO-class Supercarrier that had been constructed shortly after the war's end. With the support of many former arms companies operating on former Covenant worlds, their amassed force would be enough to glass both Sanghelios and Earth if left unchecked. Rather than risk a full-scale attack, the Office of Naval Intelligence deployed the three SPARTAN-II's in-system to kill Meridus and stop his plans for invasion at any cost. 
After arriving on a Prowler utilising highly-advanced cloaking fields, the three Spartans made use of a distraction by several UNSC vessels to land on the nearby planet in secret. Without any contact at all with command, Marco and the others only had orders to succeed at any cost. As with any high-risk, low-survival odds mission, Marco complained, Jax made a joke of it, and Kane ordered the pair of them to focus on the task at hand. For seven days the trio trekked across the colony, avoiding contact with the local Jiralhanae villages while living mostly off rations and wild animals. Eventually they arrived near Meridus' fortress and managed to enter through a waste disposal pipe in a nearby river. While the Jiralhanae warlord had enough defences to fend off a large fleet-based attack, the security measures against enemy infiltrators were sub-par and the SPARTAN-II's easily made it into the base after blasting through a pipe with a shaped charge and eliminating the nearby guards before they could raise the alarm. Covered in sewage, the armoured supersoldiers cut a bloody swathe through the fortress' defenders until they reached the command room where Meridus was supposed to be. The Jiralhanae was not present, though the controls to his base defences were. While Jax and Marco held off enemy reinforcements, Kane was able to activate several AA guns to fire on their own fleet in orbit.
With their foes in disarray, the Spartans fought their way to a nearby landing pad and hijacked one of Meridus' personal shuttles to escape the colony as several of the orbiting ships began to return fire on the base, severely damaging the fortress and the surrounding area. As Meridus had not been present at his fortress, Kane reasoned that he would most likely be aboard his Supercarrier, Return to Glory, attempting to direct the invasion fleet. In the confusion, the flight controllers aboard the ship believed that the incoming ship contained their leader and allowed them to land; they did not realise their mistake until Marco, Jax and Kane had already slaughtered the greeting party in the hangar and were working their way up the massive ship. Fearful of the Spartans' progress, Meridus dispatched groups of veteran Jiralhanae warriors to kill them while he ordered his fleet to initiate a slipspace jump towards Sanghelios. Before that could occur, several dozen ships appeared insystem, belonging to both the UNSC and United Sangheili. As the battle raged on outside, Marco and his comrades fought their way through Meridus' finest, their augmented bodies and power armour making short work of the soldiers before blowing their way into the bridge. As per his rank and status, Meridus was no easy pushover in combat; an incredibly powerful energy shield coupled with a modified Gravity Hammer made it a difficult battle for the Spartans. After Jax was nearly killed by a lucky hit and Marco was thrown across the room by the raging chieftain, Kane was able to change the ship's course on an unstoppable impact run with the planet itself.
Realising that they had little time to escape, Marco and the others fled from Meridus before he realised he had been locked out of his own bridge console, and soon gave chase to the Spartans. The sudden death dive coupled with multiple MAC round hits badly damaged the Return to Glory, which had begun to break up as it entered orbit. Meridus was almost able to catch up with the retreating Spartans, only to run directly into a trap set by Marco - C-12 charges rigged to blow through the ship's outer hull. Though his shield protected him from instant death, the Jiralhanae leader was blown out of the ship and died as the trio escaped in the same shuttle they arrived in. As they approached the joint UNSC-Sangheili fleet, the Spartans identified themselves to avoid being blown to pieces and were eventually picked up by a nearby Cruiser. ONI congratulated Marco, Kane and Jax on a mission well-done, as the three of them had managed to thrown Meridus' forces into disarray just long enough to be vulnerable to a massive counter-attack. The Supercarrier's impact had killed thousands of innocent Jiralhanae colonists on Sundered Heart, though ONI cared little for their lives and Marco had long since learned to keep his opinions on such matters to himself.
===Operation: GOLGOTHA===
In January of 2555, the Office of Naval Intelligence's investigation into the mysterious figure known as Magnus had turned up few leads, with many believing that the name was merely a pseudonym conjured up by rebels and criminals to give a name to the perpetrator of several terrorist attacks over the years. This changed when the SPARTAN-III's of Shrike Team were able to successfully capture one of his agents alive during a raid in the Outer Colonies. After a lengthy interrogation at the hands of ONI, the agent revealed that Magnus was not only real, but was conducting a massive operation involving dozens of criminal and rebel groups, the likes of which had never been seen even in the days when the United Rebel Front was at its full strength. With the location of these groups as the tip of the iceberg, ONI began to mobilise dozens of its top agents to infiltrate and destroy them from within. Among those agents was Marco, who was chosen to go undercover for the first time in years.
In spite of his noticeable stature and scars that would arouse suspicion, ONI's Section Two was able to come up with a lengthy background for the Spartan as a career criminal and hitman operating in the Outer Colonies. Part of Marco's cover story was that he was a steroid abuser with a history of violence; strength enhancers and other illicit drugs being used as an excuse for his appearance and to ensure that his new employers knew that he was a force to be reckoned with. Lastly, Marco was given the name 'Simeon Moritz' to use while undercover. After arriving on in March, he spent several weeks working illegally as a labourer in a local foundry before attracting the attention of one of the planet's more notorious criminal factions. Having spotted 'Simeon', a number of armed men brought the supposed criminal to a nearby warehouse where he met with Gordon Mills, a high-ranking member of the organisation who offered Marco a job offworld working for their leader. He accepted, and was taken aboard a freighter the next day to the Caucasus Station, a sprawling asteroid settlement home to thousands of people outside UNSC-controlled space. Mills would use Marco as muscle for several low-key operations there for nearly a week before their leader arrived.
The head of the Crimson Star crime syndicate was a woman named Patricia Hurst, a little-known individual even by ONI who met with Marco and a number of other recruits in a secure room on the station. Hurst explained that they would be participating in a large deal with the United Rebel Front, which had greatly diminished in power since the end of the Human-Covenant War. In exchange for a large sum of money, the Crimson Star was to provide military-grade equipment to the rebels in preparation for a future attack. Unable to contact his backup in any way, Marco played his part as dumb muscle for the group until their meeting date was revealed, and the man in charge of the exchange: Magnus. As they began loading up their stolen equipment for the deal, the Spartan plotted to singlehandedly sabotage the Crimson Star's plans in an attempt to bring down both their organisation and Magnus' forces in a single day. Though he was deprived of reinforcements and his MJOLNIR armour, Marco privately believed that his chances of success were fairly good as the meeting date with the URF approached.
Due to Marco's excellent results and imposing stature, Hurst chose him to act as one of her personal bodyguards during the deal in case of any arguments. Wary of a possible ambush, he suggested that he and Mills investigate the meeting area several days in advance to ensure that their URF contacts would not set up a trap there ahead of time. Unbeknownst to his employer, Marco was able to set up several blocks of C-12 explosives around the lower levels of the station the meeting was being held in, and eventually reported to Hurst that there would be no problems on the day of the deal. Though unable to contact the UNSC directly from the Caucasus Station, Marco met up with Kyle White, an undercover agent from ONI's BRUTUS division in a bar the night before. While his contact could not do a great deal and had to avoid blowing his cover, he was able to procure some weaponry and armour for Marco from the black market; two 'snapshot' pistols, a number of plasma grenades, and a modified T-55 Storm Rifle. Upon returning to the Crimson Star's base, Marco explained that he had overheard a rumour that the URF intended to seize the station following the deal, and were bringing several hundred soldiers to do so. 
While apprehensive about Marco's information, Hurst and her followers refused to take any chances and mobilised the entirety of the Crimson Star's forces to deal with any potential attack. At the same time, Kyle White had slipped information to some URF informants that the criminal organisation intended to betray them as soon as possible. As the deal took place, Marco stood back as the initial dealings took place, waiting for the arrival of Magnus. Before long, a very tall, heavily-built man entered the meeting, surrounded by bodyguards. Though Marco had orders to immediately attempt to take down the elusive terrorist on sight, he hesitated. Not only did he recognise the man, but he had once been friends with him; it was none other than Jack-085, who had supposedly died on Endrin in 2550. Watching from the sidelines, Marco took note of how Jack appeared to have undergone extensive modifications since their last encounter, considering his prosthetic legs and heavy cybernetics dotting the rest of his body. Eventually, 'Magnus' caught a glimpse of Marco out of the corner of his eye and immediately recognised the SPARTAN-II. Without hesitation, Marco detonated the C-12 charges, turning most of the warehouse into a blazing inferno and badly destabilising the entire level as all hell broke loose. URF and Crimson Star forces turned on each other in an instant, and despite Marco's best efforts Jack managed to flee. While making his way to the upper levels in pursuit of Jack, Marco ran into Patricia Hurst, who ordered him to join her forces in taking the Caucasus Station for their own. In response, he killed her and her entourage, effectively ending the threat of their organisation immediately. 
With the two forces clashing across the sprawling station, Marco had a hard time chasing his former friend. While the Crimson Star were better-equipped, the URF's tactics and sheer numbers gave them a clear advantage in the resulting battle. The Spartan was able to finally confront Jack as he entered the hangar bay, a brief but intense firefight between the two Spartans tearing the room apart before Marco managed to blow one of Jack's prosthetic hands off with a bolt of plasma. Before he could deliver the final blow, Jack managed to board a nearby freighter as it prepared to take off, escaping the station and the wrath of Marco. With his mission more or less complete, Marco managed to contact Kyle White once more and the pair left in a small freighter before jumping to Slipspace. Upon his return to Earth, Marco was congratulated for his efforts in bringing down the Crimson Star, though some sources indicated that this shift in the balance of power had placed the United Rebel Front in control of the Caucasus Station. Furthermore, Marco's report of Jack's survival to the was met with heavy scrutiny; Admiral , the head of ONI, assured Marco that Jack's death had been all but confirmed years ago when her agents had examined the remains of the Hephaestus Array on Endrin's surface. Nonetheless, the possibility that Jack had survived to become Magnus was taken into consideration by the Council at the behest of Admirals and John Hawkins, who promised that the matter would be looked into. Marco would later contact Jax-007, Kane-098, Elena-071 and Hank-136 in private about their old friend's return. While both ONI and the UNSC would take years before publicly revealing Magnus' true identity as Jack-085, Marco ensued that his Spartan comrades knew exactly who they were dealing with.
===Mission to Mamore===
In 2556 the location of Roger Maxon, a prominent recruiter for the New Colonial Alliance, was finally pinpointed by ONI. He had travelled to , a turbulent colony with a long history of anti-UNSC sentiment. The rebel leader was supposed to be directing a rally in the city of Agadir to gain support for their cause. Due to the high possibility of Mamore attempting to secede from the UEG's control again, Marco was to kill Maxon and cause havoc in the area before extracting safely; a larger UNSC force would only cause more trouble if it intervened. After spending several days getting into position near the rally and laying a series of explosives along the nearby road, the SPARTAN-II launched his attack on Maxon's convoy as they began to leave. While he was successful in destroying an armoured vehicle and the main armoured car, Marco soon realised that Maxon was hiding among his troops in the transport trucks, and fled the area as the Spartan began his pursuit. 
While he successfully avoided NCA troops in Agadir, Marco was held up on the road as the rebels deployed two mechs to take him down. Though he was heavily outgunned, the Spartan managed to board and punch a grenade into one of the rebel vehicles, destroying it. Before he could face the second, it was hit with a volley of missiles and destroyed. Marco was greeted by a group of independent humans, led by none other than an old acquaintance of his: Amanda Wade. While there was some initial confusion, Amanda asked for Marco's assistance in another task. As he felt that Maxon would only be made a martyr if he were assassinated, the Spartan allowed his quarry to escape while he assisted Amanda and her comrades in rescuing a man named Ash Mitchell from an NCA-run prison nearby. While he knew of Mitchell's involvement in a publicised attack on Circumstance known as the 'Kuiper Massacre' earlier that year, Marco was willing to help Amanda and joined a young assassin named Winston Zhou to launch an attack on the fortified base. Together the pair decimated several enemy platoons heading their way before spotting Mitchell, who had escaped himself and was attempting to flee through the nearby snowfields. Seeing that he wouldn't get far without help, Marco set off on his own and eliminated several rebel squads before saving Mitchell from a group of enemy soldiers. Mitchell, who had evidently suffered from torture and mutilation from his time in the prison, threatened to kill himself, though Marco talked him out of it long enough for Amanda to arrive and convince him to join her crew. Their quarry soon passed out from blood loss, and Marco handed him over to Amanda as her ship, the Dynasty arrived on Mamore. After a brief conversation with her, the pair on good terms for once; Marco promised not to reveal what had happened on the planet to his superiors. While he reported his mission as a failure to ONI when he returned, Marco credited himself with the destruction of the NCA's prison camp and several hundred soldiers, which drastically reduced their effectiveness on Mamore.
===Avalon Incident===
Following his failure to kill Roger Maxon, Marco was temporarily reassigned to the Department of Recolonisation and Exploration, or DRE, as a form of punishment from ONI. Marco did not mind this, and joined the crew of the UNSC Demeter, a scouting vessel that was assessing colonies glassed during the Human-Covenant War for possible resettlement and terraforming. During this time he worked with Iris Touré, who led the exploration vessel and proved to be an intellectual sparring partner for the venerable Spartan. While Marco initially had some misgivings about Touré and believed her to be an ONI agent, they soon became friends after discovering that they held similar views on colonial self-rule. Their vessel arrived at the abandoned colony world of shortly after, and discovered an independent colony there named 'Avalon'. Upon landing, it was discovered that the colony consisted of both Humans, Unggoy and a single Jiralhanae, and wished to retain independence even if the UNSC moved to recolonise the rest of the planet. While Touré spoke with the supposed leader of Avalon, Marco encountered Amanda Wade once again. They spoke for some time before the Demeter departed the planet, Marco now worrying about his sister's life and the lives of those dwelling in Avalon. He confided in Touré about how ONI may deal with the colony, prompting her to head straight back to Earth where she intended to deliver a speech to the UEG to raise public awareness of Avalon and similarly independent colonies.
Shortly after their arrival back on Earth, Marco was contacted on his personal communicator by agent Kyle White of ONI's BRUTUS division as he and Touré visited a coffee shop in New York, several hours before she was due to make her speech. White informed Marco of an impending attempt on Touré's life and instructed that the SPARTAN-II move away from his protectee. As he did so, the coffee shop was destroyed from within as an explosive device triggered, instantly killing Touré and dozens of civilians. While he first feared it to be an attack by the NCA or some other terrorist group, a car soon pulled up carrying White and Elena-071, who swiftly escorted Marco away from the scene before the police could arrive and informed him that Touré's death was an action ordered not only by the head of BRUTUS, but by CINCONI herself. As they drove off, White and Elena explained how in spite of Touré's best intentions, the UEG could not be further fractured by newly-independent colonial worlds and that it was a sad necessity to keep Humanity united. Furthermore, the attack would be blamed on Anatoly Kustentov, a rogue BRUTUS agent who had recently been recaptured and would be discreetly executed to appease the populace, while making for great anti-Insurrectionist propaganda. While utterly disgusted by the callousness shown by White in regards to the woman's life and the extreme measures taken by ONI, Marco forced himself to accept what had just happened as little more than a change in his mission's parameters and did not openly question his new orders. Nonetheless, the death of Iris Touré would forever haunt Marco, who had suddenly lost one of the very few non-Spartan personnel who treated him as a friend. Though he had always been embittered towards ONI, the personal nature of this incident was not something he could easily forget.
Shortly after Iris' death, Marco discovered that Avalon had been attacked and destroyed by the Office of Naval Intelligence's own forces. Instead of hearing about it through Elena or his superiors he saw this through footage that had been leaked from Avalon itself during the attack, making it blatantly clear who the perpetrators were as they massacred most of the populace. While officially the operation was labelled as a counter-insurgency mission, there were mass protests across multiple worlds following this, which only served to strengthen the New Colonial Alliance's political position. Initially believing Amanda to have died, Marco received a video message that had been sent to him from Lodestone in the Outer Colonies and intercepted by Elena before ONI could access it. Though brief, it showed that both Amanda and Ash Mitchell had survived the attack, and contained a statement from the two declaring that they would continue pursuing Magnus before hunting down those responsible for Avalon's fall. Though worried for his sister's welfare, Marco knew that there was nothing he could do for her and deleted all trace of the message before getting back to work.
===Southerness Incident===	
Following the in July of 2557, Sigma Team was kept on-station as reports of the newly-encountered Forerunner began to spring up around the Outer Colonies. After several sightings confirmed that they were aligned with Covenant Warlord faction, the SPARTAN-II's were stationed aboard a Prowler to await news of any further attacks. On August 17th, several Covenant ships arrived over the newly-colonised world of SouthernessSoutherness is the name of a town the author would often visit while on holiday as a child. with the intent of wiping out the settlers there. With UNSC support more than a day away, Sigma immediately moved in to assist, having been monitoring the planet beforehand. With a lot of ground to cover, Marco, Kane and Jax split up after landing in an .
		 
Scouting out the coastline Southerness had been built on, Marco discovered a number of being led by a group of Sangheili Zealots. Watching from afar, the Spartan saw that reports of them massacring civilians were incorrect; they were enslaving Human colonists. After relaying this to Jax and Kane, Marco moved in and quietly dispatched several guards en-route to the Covenant's vessel, an old . Unwilling to let them escape with any more captives but aware that he would die if he tried a head-on attack against the well-guarded vessel, Marco covertly set up demolition charges beneath a group of nearby and waited for their occupants to return, drawn by news of Sigma's attack on their comrades in the settlement. As they set off the charges detonated, killing dozens of Covenant soldiers and forcing the rest back towards their vessel.
 
To Marco's surprise, the corvette immediately took off instead of assisting the remainder of its forces on the ground. It was around this time that the surviving Promethean forces vanished, presumably teleporting aboard the ship before they could be felled by the Spartans. Upon returning to the settlement and regrouping with the rest of Sigma, Marco found that barely a third of the colony's populace had survived; the rest had been either killed or taken by their attackers. Some colonists tried to blame the Spartans for their misfortune, prompting a hasty exfiltration as Kane assured them UNSC reinforcements were en-route to help rebuild and reinforce the heavily-damaged town.
 	
After returning to Earth, Marco and the others were debriefed and spent several days waiting as ONI tracked the fleeing Covenant vessel. Eventually, it was tracked to an area of lawless space, far away from any known outpost belonging to Jul 'Mdama's allies. A spy probe was able to track the corvette as it settled on a nameless asteroid base. This strange behaviour was noted and sensing that the ship may have broken off from Mdama's main force and gone rogue, ONI dispatched Sigma to track down the Sangheili slavers and destroy them.
 
===Operation: RAILROAD===
Within a week, ONI had been able to track down the enemy slave ships to a remote location on the very edge of Human space. As it turned out, the slavers had been using colonies abandoned during the Human-Covenant War as temporary bases and meeting points, where they then sold their cargo to both Kig-Yar Pirates and Jiralhanae warlords. Entering the system alongside a small battlegroup, Sigma Team landed quietly on the planet and prepared to launch an all-out attack on the slavers from the air, utilising to launch a quick strike while Marine forces moved in for a frontal assault. 
While the slaver camp was well-defended, the speed and energy shielding on Sigma's Wasps allowed them to easily break through the outer perimeter, launching precise missile strikes that destroyed AA guns and other ground defences as the main attack force neared their location while keeping their fire well away from the slave pens. While Kane and Jax maintained their speed and high altitude, Marco moved in low to mow down the fleeing slavers with his aircraft's machine guns and was struck numerous times by plasma fire. His Wasp's shields were eventually dissipated under heavy fire and as he rose away from danger, a well-aimed plasma grenade smashed open the Spartan's cockpit window and badly damaged his engines. After taking more fire, Marco was forced to leap from his Wasp after sending it on a collision course with the slavers' barracks, kicking his MLJONIR suit's thrusters into gear to land safely as he moved to engage the enemy on foot. 
After being utterly decimated by the surprise attack from the Spartans, the Sangheili slavers were in complete disarray, with most fleeing towards their ships as Marco moved into their base alone. The SPARTAN-II showed no mercy to anyone in his way, brutally killing many foes during his rampage. After descending several levels, Marco discovered a massive cavern housing the same DAV-class corvette they had encountered on Southerness. As he approached, the Sangheili were able to summon their final group of Prometheans to engage the Spartan while they loaded up their vessel and fled the planet. Despite his best efforts to board the ship, killing a number of Armigers before a trio of Knights blocked Marco's path. While his enhanced speed and reflexes allowed him to match the hulking constructs evenly in combat, he was outnumbered and heavily outgunned in the engagement and eventually forced back. As they closed in for the kill, Jax and Kane arrived to save their friend, catching the Knights off-guard and swiftly eliminating them with a fusillade of well-aimed gunfire. 
As the corvette lifted off and moved out of the cave via a large entrance blasted into a mountainside, Marco and the others contacted the UNSC battlegroup in orbit. Though fast and armed with plasma weaponry, the slaver vessel was no match for twelve pinpoint MAC blasts and was utterly obliterated as it tried to escape the planet. With the current threat more or less annihilated, Sigma Team moved to secure the camp as Marine reinforcements arrived. In addition to numerous Human slaves, there were a number of , and kept there until an auction was held. Upon freeing a group of Human slaves, they discovered that one of them - a middle-aged man with his tongue cut out - had been a former UNSC officer after the discovery of a implant in the back of his skull.
After personally escorting him to an orbiting Destroyer after a Pelican arrived to extract them, Marco and the others learned that he had been declared KIA back in 2540. It soon became apparent to Marco that the former slave was seemingly unable to recall his past in great detail; the ship's physicians believed this to be the result of a high-level neural paralysis dart that had wiped away a great portion of his memories. As ONI agents soon arrived to take him into protective custody, the former slave was able to recall a single name: The UNSC Kuwabara.
===Finding the Kuwabara===
Sigma Team had little luck in tracking down the missing vessel, which aside from a few scant mentions in old files seemed to have vanished entirely from the records. Worse still, their prisoner died shortly after being taken into custody, leaving Marco and the others with few leads. While eager to continue the search, Marco eventually admitted that it seemed like a pointless endeavour and would continue operations alongside Sigma for a number of months. It was not until May of 2558 that the Kuwabara's trail was picked up again, prompting their immediate departure to the glassed world of . After a surveillance probe picked up signals pertaining to the missing vessel, ONI had dispatched a group of scanning ships to survey the planet until they found the source: a military bunker, buried beneath the planet's scorched surface for years. Marco, Kane and Jax were the first to move in, and supported by their new Smart AI, Iggy, gained access after finding that the base was still powered. 
Initially seeking to secure the base so one of ONI's science teams could plunder it for information, the Spartans eventually found themselves in a control room overlooking a massive hangar, and confirmed that their prey was in fact a Halberd-class Destroyer that had been extensively modified to fulfil a Prowler-like role. As they had Iggy scour the bunker's databanks for information, Sigma Team were briefly contacted by an unknown individual over the base's intercom who put the entire facility into lockdown before initiating a sequence that would detonate the nearby fusion reactors. The trio of Spartans were able to escape the command room through a nearby window and ran the entire length of the hangar bay before the bunker self-destructed, barely making it out alive through a gap in the damaged entrance doors. After surviving the attempt on his life, Marco agreed with Kane's belief that their attacker had likely been someone with connections within ONI, and after relaying what little data they recovered to Elena-071, set out alongside his fellow Spartans to hunt down the perpetrators.
The Spartans would then travel to , having used the information from Sansar to look into this mysterious faction themselves. As time was of the essence, Marco and Jax were forced to go undercover themselves on one of the planet's many resorts after arranging a meeting with one of the group's contacts there. After meeting with a woman named Melissa Aldenkamp, who handled their smuggling operations while acting as a high-ranking member of a popular resort's management team, Marco and his comrade began to question her on their operations while pretending to be part of the rogue faction. The pair kept up this act for some time and were given access to a ledger of deliveries organised by Aldenkamp, though after inquiring into one name - 'Mulberry Field' - Marco realised that they had blown their cover and swiftly eliminated the woman's bodyguards before interrogating her further. To their surprise, Aldenkamp believed that she had been working for ONI and identified her main contact as a Spartan named 'D'Artagnan'.
Before they could inquire further into Aldenkamp's situation, Marco and Jax received a warning from Iggy that they were about to be attacked and took cover as part of the warehouse they were meeting in was struck by missiles from a UNSC dropship. Lightly-armed and out of armour, the Spartans chose to flee rather than fight, with Kane-099 providing support from afar with a heavily modified ARGUS drone. As they left the building they were attacked by an armoured Spartan, who shot Aldenkamp and would have killed Jax were it not for Marco's quick actions in tackling the foe and firing into his shielded visor to give his friend time to escape. Unable to tackle this foe on even ground, Marco and Jax used this time to escape, running through the nearby forest and back towards the resort with not one, but three enemy Spartans in hot pursuit. The pair might not have escaped were it not for Kane providing fire support against their attackers and a modified circling the area. Taking cover on the resort's outskirts, Marco held his position until Kane's drone managed to down the dropship with a direct hit on its cockpit.
While they soon arrived at the resort, Marco and Jax discovered that these renegade Spartans were somehow jamming their long-distance communications, as their requests for support from a Sahara-class Prowler in orbit were being completely ignored. Though Sigma Team intended to suit up and turn the tables against their foe, the sudden arrival of a Condor nearby ruined their plans, as they were forced to watch their enemy escape from afar. After finally managing to call for a pickup, Marco presented his team with the only source of information they now possessed: Aldenkamp's ledger. While several prominent locations relating to the rogue ONI cell were listed aside from the itinerant 'Mulberry Field', the Spartans received a sudden message to return to , where Elena-071 had made a breakthrough.
After meeting with Elena at Aldrin Base, a secure ONI facility on Luna's surface, Sigma Team were given access to a top-secret data library known as the Grey Archive. While they were on Sundown, Elena had pored over numerous old documents pertaining to the owners of the bunker on Sansar and had found a group of half-deleted files on 'Project RED CELL', which had been officially disbanded in 2532. While this identified their attackers as a former ONI black ops group that specialised in testing the security of military installations against potential Insurrectionist attacks, Elena then informed them that the files had clearly been tampered with and were incomplete. Before they could discuss the issue further, they were contacted by Alexander Redford of BRUTUS, who had tracked down a pair of missing agents linked to the RED CELL group to Biko. Seeing this as a chance to gain a proper lead, Sigma set out with Elena to intercept them.
Taking Elena's personal Prowler, Heavens Asunder, the Spartans arrived on the recovering colony world the following day and landed some distance away from an isolated farm where their targets were located. Checking the files on their targets - Spartan Violet-B039 and BRUTUS agent Jill Urbach - beforehand, Marco believed that they would meet heavy resistance from the pair, who had gone missing after the massacre of a Marine garrison on Erdenet a few days prior. Landing far away from their target location to avoid detection, the four Spartans surveyed the area for some time via high-altitude surveillance drones and discovered a heavily-armed enemy force approaching the farm. Correctly believing it to be RED CELL, Sigma moved in quickly and ambushed the group as they surrounded the main buildings. 
Moving in alongside Jax, Marco swiftly eliminated several enemy soldiers before the rest pulled back into defensive positions. The firefight proved to be surprisingly intense, though Sigma Team had the well-trained soldiers heavily outmatched from the start. Circling around, Marco was informed that an enemy Spartan had entered the battle and was engaging Violet-B039 in combat. Elena ordered the team to not attack the SPARTAN-III, while Marco had orders to take the attacking Spartan alive if possible. Marco smashed through a wall just in time to save Violet from execution, and though he intended to swiftly bring down his foe found himself engaged in a surprisingly difficult close-quarters battle. Disarmed of their weapons, the pair fought with knives and fists for some time. After attempting to end the fight with a quick throw, Marco found his attack countered and was thrown to the floor. The other Spartan taunted him, though after Elena and Jax arrived he quickly surrendered. With a sudden feeling about who his opponent was, he urged his comrades to lower their weapons as the enemy Spartan removed his helmet. For the first time since the Fall of Reach, Marco found himself facing his old friend Wulf-041.
As the rest of Sigma arrived, Wulf surrendered to Marco and allowed the other Spartans to take him prisoner. While the survivors at the farm were rounded up, he revealed that while he and the SPARTAN-III's lost in New Alexandria had come close to death, they had been rescued by an element of the Red Cell group led by none other than Derek-142, a former member of Project SIGMA that had disappeared shortly after their augmentations in 2525. Furthermore, Wulf had been part of Derek's plans to stage a coup within ONI using Project OVERSIGHT, a massive repository of data that he had been using to spread misinformation and redirect assets within the organisation. While Kane was of the opinion that Wulf was a traitor, both Marco and Jax were willing to welcome back their old comrade with open arms and chose to trust him as he admitted that he was against Derek's plan and would stop the renegade Spartan at any cost. While Elena took two of their undercover agents back to the Sol System with the intent of warning ONI's leaders, Marco's team set out alongside Urbach, Violet and a former smuggler named Gustav Klein to intercept Red Cell before they caused any more damage.
Arriving in the remote Isimud System a day later, the Spartans would discover a lone communications station that had been taken over by Red Cell. Moving swiftly to prevent Derek-142 from potentially distributing decades of classified military secrets over unsecured civilian networks, Marco and the rest of Sigma allowed Wulf, Urbach, Klein and Violet to move to the control room while they covertly exited their Condor and worked their way through the occupied station. Avoiding the guards and renegade SPARTAN-III's, they were able to secure the communications centre and deactivated all long-range COM systems before sending Iggy to assist the others with cutting off Derek's own AI. While successful in their part of the operation, Sigma soon learned that Derek had escaped a firefight upstairs and was fleeing towards their location. 
With news that Red Cell's other Spartans were also on their way, Kane dispatched Marco to intercept Derek while he and Jax dealt with the SPARTAN-III's. Tracking his former comrade through the station, Marco ambushed Derek and his personal guards in a corridor, and after killing several of them convinced the rest to turn on their leader in exchange for amnesty from the UNSC. To his surprise, Derek immediately killed his underlings, though it gave Marco time to race towards the traitorous Spartan and engage him in close combat. While he clearly outmatched Derek in an even fight, Red Cell's leader possessed several prototype systems built into his MJOLNIR suit that gave him an edge against Marco. Contending with both a powerful hard light shield and a directed constraint field, Marco nearly overwhelmed Derek before he managed to immobilise him with the device. Before he could finish the SPARTAN-II off, Derek was attacked by Wulf-041, who grievously injured him with a direct hit from a Spartan Laser. 
Freed from the constraint field, Marco swiftly subdued Derek, whose injuries were severe but not fatal. Furious at what the other Spartan had done, Marco taunted his captive after contacting Kane and Jax, who had convinced the other SPARTAN-III's to stand down peacefully. Unaware that Derek still had access to his short-range COM, Marco was unable to stop him from having his last loyal subordinate trigger a failsafe that killed every last remaining non-Spartan Red Cell operative via microbombs placed within their neural implants. Though disgusted at Derek's final act of defiance, Marco did not harm him further and ensured that he was transferred safely to a medical suite aboard a newly-arrived ONI frigate. With Red Cell all but destroyed and their OVERSIGHT plan halted, the mission was deemed a success. 
Following the mission, Marco and the rest of Sigma Team would head back to the Sol System, where they gave testimony in favour of not only Wulf, but for Dan-A105, Chris-A189 and Eugene-A133. To his surprise, they were cleared of all charges after only a few days of deliberation, though they were to be placed on probation before being cleared for active duty once again. Remaining at the Spartan-run Denegroth Station on Europa, they would officially welcome Wulf-041 back into Sigma Team before setting out on yet another mission. Overjoyed to have his old friend back, Marco was at his happiest for the first time in several years.
===Created Conflict===
In October of 2558, Marco was stationed over aboard the UNSC Peacemaker, an with a sizeable SPARTAN-IV contingent. With Kane outsystem, Sigma Team was using its downtime to conduct simulated '' exercises with these younger Spartans on the ship's combat deck. It was in the aftermath of one of these sessions that the Sol System was suddenly invaded by several , which quickly disabled any notable resistance across the system. After dealing with the warship's rebellious AI, the Peacemaker's commanding officer, Captain Al-Sayed, initiated a immediate slipspace jump that took them out of the system, sending them off on a random trajectory before the warship could be disabled. While he understood Al-Sayed's decision, Marco felt extremely guilty about leaving behind not only Jax and Elena, who were stationed on Europa and Luna respectively, but his brother Michael and his family, who were now stranded on Earth.
Cut off from HIGHCOM and most of the UNSC's armed forces, they would make three more jumps to lose any pursuers before proceeding to a remote rendezvous point, where they would await friendly contact. While no military reinforcements joined them, the Peacemaker soon encountered an ONI prowler, which had captured a civilian transport craft and signalled the carrier for assistance. Marco, Wulf and Fireteam Whiskey were dispatched to greet the ships as they were guided into the Peacemaker's hangar bays, though the heavy Spartan presence for the civilian ship raised Marco's suspicions. When the craft landed, Marco was shocked to see Ash Mitchell and Amanda Wade disembark, led off the ship in handcuffs by Violet-B039. Faced with the prospect of his younger sister's near-certain demise in ONI's hands, Marco briefly considered rescuing Amanda, though he quickly dismissed these notions. Already filled with turmoil at the sight of Amanda's capture, Marco was then met by the sight of the civilian craft's captain: Jack-085. 
Expecting his nemesis to come out fighting, Marco was surprised when Jack instead surrendered alongside his co-pilot, allowing himself to be taken into custody. Knowing how dangerous the renegade Spartan could be, Marco urged Spartan Commander Mikhail Schultz to allow him to execute Jack, but these requests were swiftly denied. Much to his chagrin, Schultz ordered that all the prisoners be taken to the ship's brig and ordered Marco to remain on the ship's Spartan deck, where he would remain for over sixteen hours before any news reached him. Wulf informed Marco that Jack had been entirely cooperative, and informed him of the true extent of Jack's tremendously advanced cybernetics. Shortly after, Marco was called to the Peacemaker's brig, where he and Captain Al-Sayed met with Jack in his secure cell to discuss his terms of surrender. Unsure of Jack's plan beyond an inevitable escape attempt, Marco urged Al-Sayed to dispose of him immediately, but was again denied due to Jack's value and knowledge of the United Rebel Front's hidden bases. After some negotiation, an agreement was made in which Jack would lead the Peacemaker to the URF Hydra, the rebel group's mobile flagship, and give the warship a safe place to hide once the URF's scientific leadership was dealt with. Marco was shocked when Jack requested not his freedom, but his life in return.
Several days later, Marco and Wulf would join Jack on his infiltration mission to the URF Hydra, with Fireteam Whiskey acting as support. To ensure Jack's cooperation, Marco had him fitted with a linked to his suit. To fool the rebels aboard the stolen frigate, Marco would play dead, pretending to be a Spartan killed by Jack and brought back for study by the Omega Group, the URF's top scientists. While he had his doubts, the ruse worked, and after docking with the Hydra he was taken to the ship's laboratory. Listening in as Jack spoke with Doctor Simon Petrovich, the URF's lead scientist, he discovered that the Omega Group intended to parlay with the Created, seeking amnesty as their fight was with the Unified Earth Government, not Cortana's new empire. As the conversation worsened, the Peacemaker suddenly arrived in-system and fired on the Hydra, disabling the smaller vessel with its point-defence guns.
Taking advantage of the sudden chaos, both Marco and Jack acted as the ceiling above them half-collapsed. Marco quickly disposed of Petrovich's guards, seizing a weapon while Jack entered Petrovich's lab and killed him. With Jack's part of the bargain complete, the pair took over the ship's bridge and demanded that the surviving crew surrender peacefully. Despite their hatred of the UNSC, most of the rebels did as ordered at Jack's request, and troops from the Peacemaker soon arrived to secure the vessel. The sole surviving URF leader, General Miriam Bakos, was also taken into custody by the Spartans. Returning to the Peacemaker, Marco harshly berated Iggy for firing on a ship with friendlies aboard, especially considering how many non-combatants had been living on the Hydra. Negotiations soon ensued between Bakos, Jack and Captain Al-Sayed, and the decision was made to attach the crippled Hydra to the carrier and keep its crew there as prisoners for the time being. Jack, surprising Marco once again, actually held up his end of the deal, and revealed the location of a remote URF-controlled colony called 'Persistence', far outside the confines of occupied space. With no way of linking up with the remnants of the UNSC Navy, the Peacemaker soon set off for this new world. Despite his lingering hatred for Jack for his many crimes, Marco realised that they had worked well together on their mission, making him nostalgic for the days of their youth when they had formed a nigh-unstoppable team with Elena. Still suspicious of Jack's true motives, Marco resolved to watch him closely on their trip to Persistnce.
==Personality== 
During training, Marco possessed a rather rebellious attitude towards his trainers, namely Doctor Calvin Roe. Though this faded with time as his Spartan training gave him a more serious, detail-oriented mindset, he was certainly more flippant regarding orders compared to some of his comrades. Marco would adopt a rather cynical, sarcastic personality and would and would often comment negatively on his surroundings or taunt enemies in combat to gain the advantage where necessary. He was also rather vocal with his opinions on the Insurrection, seeing any who continued to fight the UNSC during the war as despicable traitors to mankind. While his views softened somewhat post-war as he encountered many individuals with genuine grievances against the UEG, Marco was firmly against armed insurrection and often worked to eliminate violent groups. He also held a very dim view of Covenant races and greatly enjoyed slaughtering enemy troops during the war. In spite of the alliance with the Swords of Sanghelios, Marco refused to trust aliens and expected their betrayal at any moment. While he was forced to work alongside allied Sangheili more than once, he remained very wary and kept them at arm's length. Even so, Marco would try follow orders diligently, though if his methods were considered unorthodox and audacious even by Spartan standards. 
After finding out about his family in 2553 Marco became very protective of them and kept in contact as often as possible. While his own brutal upbringing and military training made him unsuited to civilian life and interaction, he enjoyed being around his young niece, Kate. Outside of his biological family, Marco grew very attached to all of his comrades within Sigma Team even if he refused to show it; Wulf-041's death in particular was devastating to Marco, as it triggered his violent pursuit and the murder of Calvin Roe, which even he looked back on as something rather shameful. Though he cared greatly for his comrades, Marco had very few close friends even within Sigma, and only confided in a handful of people throughout his entire life. During training, Marco became good friends with Jack-085 and Elena-071, also befriending Nef-015 and Wulf-041, though he was always closest to Elena; his fellows often remarked on his excessively playful attitude while around her and his willingness to follow any order she gave without question. Following the augmentations, with Elena's supposed death and Jack's escape, Marco found it difficult to integrate with others. However, outside of combat, he was reasonably friendly, or at least attempted to be so. Like to most of Sigma, he made very little effort to socialise with non-SPARTAN personnel, with few exceptions.
Like some Spartans, Marco would suffer occasionally from the effects of Post Traumatic Stress Disorder after years of near-constant campaigning with few breaks from war. Both in an out of combat he often felt numbed towards events around him and disliked attracting attention towards himself, and felt unable to break out of a mindset that left him ready to kill at a moment's notice. He also suffered from what was known as survivor's guilt after witnessing so many of his fellow Spartans killed in combat and incorrectly blamed himself for the death of his friends. After Wulf-041 rejoined Sigma Team in 2558, his temperament improved greatly.
==Skills and Abilities==
During his training as a SPARTAN-II, Marco was noted for being the most tactically flexible of everyone in the Project SIGMA and was able to adapt to changing circumstances better than his team mates could due to his penchant for developing unorthodox methods of combat. However, Marco's tendency of going off alone in battle would put his team in danger several times during the Human-Covenant War, forcing him to consciously hold himself back. In spite of his seeming lack of specialisation compared to his comrades, Marco did stand out as one of the best hand-to-hand fighters within Sigma, combining raw power with prestigious skill to bring down much larger opponents in seconds; his greatest boast was an occasion where he had killed a pair of Mgalekgolo in close combat while unarmed.
The Spartan was particularly skilled in the martial art of Krav Maga, which relied on grapples and the quick neutralisation of threats, something that was critical in battle. With his SPARTAN augmentations improving his speed, strength and reaction time, Marco was a nigh-unstoppable force at close range for most enemies. 
Marco also attempted to repurpose Covenant weapons as something of a hobby, though his only notable success was customising a captured Brute Shot to fire human-made grenades during the Battle of Harpa. Though useful at the time, his weapon was confiscated and most likely destroyed upon Sigma Team's arrival to Reach in July 2552. Marco's tinkering was largely something he practised in his spare time, often attempting to improve on the efficiency of his weapons. Like all Spartans he was proficient with most Covenant weapons after years of combat experience, and attained a rudimentary knowledge of some handheld Forerunner weaponry after several encounters with enemy Promethean constructs.
When it came to plans, Marco was never quite the brilliant tactician that Fenn-145 was. His favoured strategy was to simply use overwhelming force and speed to build momentum and attain victory, not allowing the enemy a moment to recuperate or re-organise. Though charging a foe was often seen as a costly and nigh-suicidal tactic, Marco relied on his augmented body and the organisation of his fellows to get the job done, acting as Sigma Team's vanguard in many battles. Also notable among Marco's qualities was his intense resilience to pain, taking damage that would cripple or kill even Spartans in the field. During the Battle of Harpa, for instance, Marco was able to fight for several days without sleep, enduring a broken arm, barely-functioning armour and multiple plasma burns without any significant impact on his combat effectiveness. As with all SPARTAN-II's, Marco was also trained to give first aid, though it was a talent he rarely put to use in the field.
==Appearance==
Due to spending a great deal of his time encased in armour, Marco's skin was unnaturally pale while much of his muscular body was covered in scars as a result of both his augmentations and years of intense combat. While outwardly stoic like his brethren, Marco has been described as 'twitchy' by others and rarely shows signs of genuine relaxation; something he would only realise when attempting to spend time with his civilian family. Though he kept his hair close-cropped and was clean-shaven for the duration of the Human-Covenant War, Marco would eventually grow a short beard after the war's end in tribute to an old agreement he had jokingly made with Wulf-041 years before. After many years of heavy fighting on the frontlines and experiencing more combat in a single year than most soldiers would see in their entire career, Marco's green eyes acquired a constant, piercing look known as a thousand yard stare; a sign of lingering trauma from his life at war.
==Equipment==
Throughout his career, Marco has worn several different iterations of the MJOLNIR Powered Assault Armour. Enhancing his already-formidable strength, speed and reaction times, the suit has saved Marco's life on numerous occasions and has become like a second skin to the Spartan. Aside from his earliest suit, Marco has always requested that his armour be tan in colour, mostly out of personal preference. As of 2558, he has worn eight different iterations of the suit.
SPARTAN-035's MJOLNIR suits	SPARTAN-035's MJOLNIR suits	SPARTAN-035's MJOLNIR suits	SPARTAN-035's MJOLNIR suits 	SPARTAN-035's MJOLNIR suits	SPARTAN-035's MJOLNIR suits	SPARTAN-035's MJOLNIR suits	SPARTAN-035's MJOLNIR suits
Suit name 	Image 	Time Worn 	Description 	Status 	 	 	
MJOLNIR Mark IV/Prototype 	 	2526 - 2531 	The first MJOLNIR suit worn by Marco, this Mark IV iteration featured several modifications based on data from the and several other early ground engagements. As it was developed at a time where knowledge of the Covenant was still scarce and Sigma Team was primarily deployed against Insurrectionist groups taking advantage of the chaos in some Outer Colony worlds, its effectiveness was not tested until Marco's first engagement with Covenant forces in 2530. While effective in its five years of use, massive technological advancements in this short period and some plasma damage to the suit's systems after heavy fighting in early 2531 had made it somewhat obsolete. 	Decommissioned 	 	 	
MJOLNIR Mark IV 	 	2531 - 2544 	A more streamlined MJOLNIR variant based on the Mark IV's production model, this suit served Marco throughout the Outer Colony Campaigns and was able to maximise the Spartan's speed and agility in combat. While its heavy use against the Covenant saw astronomical maintenance costs for replacement parts and upgrades, it proved to be a reliable, long-lasting piece of equipment that saw Marco through well over a decade of combat. Even this suit did not last the Spartan forever, as after Marco was nearly killed in the Raid on the Umbra Tempestus in late 2544 it sustained irreparable damage and was replaced at the user's request with a hardier, upgraded MJOLNIR suit. 	Destroyed 	 	 	
MJOLNIR Mark IV/UA 	 	2544 - 2551 	The third Mark IV suit worn by Marco, this 'up-armoured' version boasted much greater protection from enemy attacks while retaining the same advantages given by his previous armour. While the helmet resembled the prototype version worn by the SPARTAN-II in the 2520s, its advanced firmware upgrades gave Marco an even greater edge in combat. Designed for prolonged, intense combat as the Inner Colony Sieges began, this suit was tough even by MJOLNIR standards and helped to amplify Marco's strength to even further levels. 	Decommissioned 	 	 	
MJOLNIR Mark V 	 	2551 - August 2552 	Given to Marco and his comrades months after the Spartan helped test prototype versions of the suit on Cronus IV, this suit not only possessed the usual interior upgrades, but had newly-developed energy shielding technology that had been reverse-engineered from captured Covenant equipment. While worn for less than a year and not cosmetically very different from Marco's previous suit aside from the helmet, his Mark V armour would endure a tremendous amount of damage throughout 2552, lasting through both the brutal Battle of Harpa and a majority of the . Following the Battle of Outpost Foxtrot-Whiskey, Marco's horribly-damaged suit was barely operable and after a visit to upgraded to a newer variant. 	Destroyed 	 	 	
MJOLNIR Mark V/G2 	 	August-November 2552 	The second version of the MJOLNIR Mark V suit, this was given to Marco, Jax and Kane during the Fall of Reach. Designed as an upgrade for the mainline suit, it mostly possessed minor firmware and shielding upgrades, but also allowed for the integration of an Artificial Intelligence construct into the suit itself. Marco would wear this suit for the remainder of his time on Reach and during their journey back to Earth. It was given some enhancements by Elena-071 during the Battle of the Zenith Complex and was vital to Marco's survival during the Battle of Second Sanctum, though the suit's newly-implemented systems began to experience malfunctions by the time Sigma Team returned to the Sol System in time for the . Its last major engagement would be the Battle for Moscow, where critical damage to the armour's outer layers and the production of newer suits made it obsolete by the time Marco arrived at PILLAR base. With few salvageable parts, this suit was disposed of by the end of 2552.	Destroyed 	 	 	
MJOLNIR Mark VI 	 	2552 - 2554 	One of a number of newly-created MJOLNIR Mark VI suits not dispatched by the time the Covenant began their invasion of Earth, Marco and the surviving members of Sigma received these upon their arrival at PILLAR base. Though lacking the specialised modifications that many Mark VI variants had, it was still a big step up from the Mark V and saw plenty of action on Earth in the final months of the Human-Covenant War. Marco would continue wearing this after the war's end while Sigma spent months clearing out pockets of enemy resistance. While it never received any major damage, by 2554 the suit had already become somewhat outdated, prompting an upgrade. 	Decommissioned 	 	 	
MJOLNIR Mark VI/UA 	 	2554 - 2556 	An upgraded variant of the mainline Mark VI armour, this version worn by Marco had heavier armour and greater shield strength, and proved useful as he and his comrades began a series of dangerous operations on the fringes of Human space. In terms of design, this armour was a hybrid of sorts between older MJOLNIR models and the newer GEN2 design, though officially it was considered a 'GEN1' suit. Considered to be a very dependable, if unremarkable suit, Marco would wear this in the field for over two years before transitioning to a new GEN2 model. 	Decommissioned 	 	 	
MJOLNIR GEN2 	 	2556 - 	Issued as part of a widespread upgrade to most SPARTAN-II and SPARTAN-III personnel still using the older GEN1 system, this armour is heavily customised to enhance Marco's main strengths - physical power and close-quarters combat - on the battlefield, and retains both the older Mark VI helmet design and chest and shoulder pieces sourced from variant. 	Active 	 	 	
==Promotions==
 Rank 	 Rank 	 Dates 
 	 	March 22, 2525—May 8, 2545
 	 	May 8, 2545—March 5th, 2553
 	 	March 5th, 2553—
==Gallery==
MARCO1.jpg|Marco, circa 2545.
MARCOG1.jpg|Marco in his Mark V armour.
MARCOG3.jpg|Marco using a heavy machine gun.
MarcoMack.jpg|Marco with Richard Mack Jr., one of the few non-Spartan personnel whom he considered a friend.
MarcoHarpa2.jpg|Marco and Wulf-041 fighting on Harpa.
Marco-Harpa2.jpg|Marco about to attack several Sangeheili warriors.
File:MarcoZC.jpg|Marco fighting alongside ODST's of Whiskey-04
File:SIGMA_MARCO_NOHELM.jpg|Marco without his armour in a training exercise, circa 2535.
File:MARCOSECTOR6.jpg|Marco fighting in 2543
File:Marco-025_H4.jpg|Marco in a GEN2 suit.
File:Marco_2585.jpg|Another GEN2 suit briefly used by Marco.
File:Marco_Top.jpg|Marco donning a very early prototype Mark VI helmet for a trial session in mid-2552.
==Trivia/Behind the Scenes==
*Marco is the main SPARTAN-II protagonist of the Sigmaverse.
*As with the rest of Sigma Team, Marco was originally created before the user joined the site for a Machinima project, in which he would have been a Spartan heavy weapons specialist. Once the project was cancelled, he and many of the other characters were heavily revised before appearing on Halo Fanon.
*This is the author's second ever page, and first character article. As such, it has undergone constant revision and improvement since its creation and was the basis for the rest of the Sigmaverse to form around.
*Marco's original Spartan tag for nearly seven years was actually 025. After the release of Halo Wars 2 and the canonical Spartan appearance, the author changed it to 035.
==List of Appearances==
*Mistakes (2519)
*Back Then (2520)
*Weakness (2521)
*Start of Darkness (2525)
*Overwatch (2546)
*Drifting (2549)
*Rebirth (2550)
*Sacrifice (2552)
*Flight (2552)
*Losing Hope (2552)
*Gaining Faith (2552)
*Breath (2553)
*Halo: Mercy Kill (2554)
*Halo: Sanctuary (2556)
*Monolith (2557)
*Respite (2557)
*Halo: Oversight (2558)
*Halo: SIGMA (2558)
*Halo: RED FLAG (Non-Canon)
*Halo Fanon: Survival of the Fittest Season 4 (Non-Canon)
*Halo Fanon: Survival of the Fittest Season 5 (Non-Canon)
*Halo Fanon: Survival of the Fittest Season 6 (Non-Canon)
*Halo Fanon: Survival of the Fittest Season 7 (Non-Canon)
*Halo Fanon: Survival of the Fittest Season 8 (Non-Canon)
==References==
Category:Sigmaverse Characters
Category:Sigmaverse
Category:Sigmaverse HCW
Category:Sigmaverse Spartans
Category:Sigmaverse PW