Cleansing of the Sin of Damnation - Cleanse and Purge: While establishing a beachhead to defend their Boarding Torpedoes, the Blood Angels detected a bank of functioning lifeboats aboard one of the ships that comprised the Hulk. It was a priority that these were rendered inoperable, before any Genestealers could use them to exit the Space Hulk and evade destruction. Though the orbiting the Strike Cruisers had weapons trained on the Hulk to eliminate any escaping craft, such fire would disrupt the Space Marines' operations and was not 100% assured.The large bank of escape pods was controlled by a central release mechanism located in a control chamber a short distance away. None of the saviour craft were capable of launching until a system override was released on the main controls. Squad Lorenzo was tasked with the mission of destroying the controls completely, in order to prevent the lifeboats ever launching. The control chamber was several hundred metres from the established perimeter and it was Captain Raphael's expectation that Squad Lorenzo would suffer heavy casualties. Such was the importance of containing the Genestealer infestation the commander judged this a price worth paying, even at this early stage of the battle.With Lexmechanics studying the layout of the Space Hulk and the early movements of Genestealers, Captain Raphael was able to predict the route of the alien attack with some accuracy. The first Genestealer assault was likely to come from the main hibernating cluster, located less than a kilometre from the landing zone. It was imperative that the Space Marines maintained the momentum of their assault rather than be pushed onto the defensive at the very outset.The expected attack route forced the Genestealers to pass through a key junction where the hulls of two starships had been compressed together. Sergeant Gideon and his squad were despatched to cover the junction and kill all aliens attempting to pass. The first Genestealer assault was effectively countered and the Space Marines were able to expand their perimeter to a position from which they could attack the dormant Genestealers.As the Space Marines moved into position, the C.A.T. unit closest to the Genestealer concentration had completed its scan of the enemy. However, the sheer density of the Space Hulk's structure prevented the Automaton from transmitting this data and it moved erratically along the corridors as it sought a suitable transmission location. Outside the embattled perimeter, Sergeants Lorenzo and Gideon were in a position to manually retrieve the faulty C.A.T. unit. The two squads converged on the C.A.T. unit's last known position from opposite directions and linked up once it had been recovered. Meanwhile, the bulk of the Blood Angels force pressed out from the landing zone, sweeping aside the alien resistance. Organised and determined, the Space Marines advanced their position by several hundred metres, whilst the Genestealer response was haphazard and ill-coordinated.With the C.A.T. reclaimed, Squads Lorenzo and Gideon turned back towards the main Space Marine defensive line. Casualties in all sectors had been low and Captain Raphael continued to rotate squads between the primary cordon and reserve to ensure that the Techmarines could affect repairs to damaged armour and re-supply the squads on the firing line.With the second wave of attacks staved off, Captain Raphael ordered his squads onto the offensive. However, even as the Genestealer attacks lessened in their intesity, a small number of aliens managed to break through the perimeter via an undetected route. Two Techmarines isolated from the other support squads went missing in action. Their Power Armour continued to transmit functioning lifesigns and Captain Raphael quickly organised a rescue response. It was unthinkable that the sacred gene-seed of the Blood Angels should fall into the hands of the Genestealers. With the majority of the force committed to securing the hibernation zone, Raphael once again looked to Squads Gideon and Lorenzo to locate the missing Techmarines. Though Squad Lorenzo located the missing Astartes, they were both sorely wounded, their armour stripped away in many places as blood trickled from large gaping slashes across their bodies. It was too late to salvage their gene-seed, as both had been infected by the Genestealers and the viability of their gene-seed was negative. They were granted the Emperor's Peace by the Blood Angels Terminators' Storm Bolters.Meanwhile, the data from the retrieved C.A.T. unit showed that the support systems of the merchant ship where the majority of Genestealers were located were serviced from a a single pumping station located near the aft of the vessel. Test releases of toxin gas brought from the Strike Cruisers had demonstrated that it was possible to poison the Genestealers. However, the concentration required was almost one hundred times higher than the fatal dosage for humans. The Blood Angels needed to secure the pumping station in order to flood the merchant ship with gas, and at the same time prevent the Genestealers from escaping once the toxin was unleashed. It was Captain Raphael's intent that a diversionary attack by Lorenzo and Gideon's squads would lure away the majority of the wakened Genestealers. If the enemy could be tricked into thinking a secondary concentration was the Blood Angels' target, the way would be open for the main force to advance against minimal resistance.During the attack on the secondary Genestealer infestation, contact was lost with the members of Squad Lorenzo. Lifesigns transmitters showed that they had not been killed, while sensorium data revealed that they were in their previous defensive positions but unmoving. As Captain Raphael absorbed this turn of events, he received new information, this time from Librarian Calistarius. Though it remained unclear how Squad Lorenzo had been incapacitated, the effect on the Space Marines' strategic situation was dire. Lorenzo and his warriors had taken a heavy toll on the Genestealer reinforcements but several hundred had survived to threaten the flank of the main attack. Brother Calistarius raced to link up with the outermost Assault Squad, led by Sergeant Leodinus. As the young Lexicanium fought his way towards Squad Lorenzo's last known position, his prescient abilities detected the unmistakable signs of some sort of alien psychic attack that was the cause for Lorenzo's disappearance. Notifying Captain Raphael of his suspicions, Calistarius was then ordered to link up with Squad Leodinus instead, but by the time he arrived, only one Battle-Brother remained alive. The two Blood Angels then proceeded to the last known location of Squad Lorenzo. Squad Gideon completed the purging of their assigned cluster, and also proceeded to move onwards to rendezvous at Lorenzo's position.