Halo: Wrong Side of Heaven

==Wrong Side of Heaven==
I spoke to the devil today, and he swears he’s not to blame
I understood, because I feel the same
“Get down!”
Explosions thundered through the air as Grant Anderson flung himself to the ground, heat washing over him as dirt and shrapnel soared through the air. Face down on the pavement of Gallahad, a sprawling metropolis on London II the marine desperately tried to regain his bearings as he scrambled to get behind a burnt out car.
Back pressed against the scorched passenger door his eyes wandered about. He knew that three floors up in the building to his back insurrectionist were posted up with a hopefully empty RPG and multiple automatic weapons. Strewn about the street were the corpses of his squad, mangled and torn by explosions.
Was he it? Grant’s gaze settled on a body he could scarcely identify, burned and mangled almost beyond recognition the sergeant’s stripes on the man’s stump of a right arm identified him as Adrian Cambell, his squad leader. Emitting a guttural snarl through the blood filling up his mouth the NCO brought up his M7 SMG in his remaining arm and made to fire.
In a flash rounds peppered the man, the bullets jerking his body violently as Cambell went limp. The rounds punched through the body armor with ease and Grant’s look of sheer terror began to transform into one of rage. It was becoming more and more clear why the UNSC had to be called in to put down the rebellion instead of the local CMA. These rebels hadn’t just found RPGs and armor piercing rounds, they’d been given them.
“Sons of bitches.” He grumbled, thumbing the COMM and opening up a line. “This Red Six, does anyone copy? Red Team is down, I repeat it’s just me send help. I repeat send reinforcements! I’m pinned I can’t-!“ The transmission cut as rounds whizzed overhead, shattering the window of the car and raining glass down onto him.
Impulsively he rolled left and peeked out from behind the bumper with rifle raised. He fired before his assailants could, spewing 5.56 from the mouth of his assault rifle. The rounds whizzed through the air and over the heads of the insurgents who shrunk into the cover of cubicles inside the office building they hid inside.
In the split second they hid themselves away, Grant rushed the door and bursting into the lobby. Anderson found himself in a heavy sprint for the stairwell. He had no plan, he was running on instinct and adrenaline. “Yo he’s inside!” Anderson heard someone yell from above him as he rushed into the stairs.
In an instant his weapon was pointed upwards, level with the head of masked insurgent. He pulled. The MA5 kicked against his shoulder and the rebel’s head jerked backward. Slumping forward the corpse fell as he ascended. “Dan?” A voice called out from further up as he cleared the landing of the second floor.
Rising towards his destination he came face to face with another masked insurgent. Lowering his shoulder and keeping his momentum the UNSCMC Corporal leveled the skinny male. In a blur of motion he brought his weapon back and squeezed. The ammo counter went lower and lower as the corpse jerked beneath him. 
“No!” Hearing the scream Grant pivoted to the right as rounds whizzed past his head. Firing from the hip he sprayed into the office and closed his eyes. Screams confirmed his hits as he pressed against the wall. Moving faster than he could imagine himself going he released the magazine and rammed a new one home, then racking the slide.
As he left the wall and entered the office area he once again raised up his weapon. Instantly a hot, sharp pain ran up his leg in the aftermath of a loud shot. But somehow the marine was unphased, letting off a quick burst into the shooter and rolling into a cubicle as more bullets screamed past.
Drawing, arming, and flinging the M9 frag grenade took a matter of seconds. And as the remaining rebels cried out in warning, Grant leaned out and put a short burst into a man standing near a busted out window who staggered back and fell, screaming the whole way down.
In the instant before detonation the marine ducked his head as the screams of rebels was drowned out by the bellowing explosion. Then it was silent. For what felt like an eternity Anderson slumped against one of the cubicle’s walls, his body finally catching up with him. 
Breathing heavily Anderson rose up, grabbing an edge and pulling himself up onto his feet. Looking down the aisle or scorched white cubicles, painted with spatters of blood from the corpses which lay about them. He’d done it. All of them were dead. 
Stepping over the mangled and lifeless bodies, Grant’s boots squelched in the puddles of blood as he moved towards the window. He tried not to look down, to see the carnage he’d wrought, but as he stepped forward pain shot through him from his leg. As he jerked forward and agony his eyes went wide.
The boy was so young, fourteen at best, lying at Grant’s feet with shrapnel in his throat. Gingerly Grant turned and lifted the mask of another. He felt his stomach churn as he unveiled the face of a young girl perhaps even younger than the boy.
They couldn’t all have been so young, these two were probably thrillseekers who’d made a bad call in the early days of their youth. Idiots, how foolish could kids be? As he began to truly look around, the scattered corpses were all so small. Too small.
What had he done? Tears welled up in his eyes as he pulled down his facemask and vomited in disgust, the bile mixing in with the blood and flesh. Stumbling back Grant moved towards the exit, vomiting again as the smell of burned flesh caught up with him. Reaching up and unclasping the helmet strap the soldier flung his helmet away as he stumbled onto the landing, looking down at the small boy lying in a bloody heap.
Child soldiers, his unit had been massacred by child soldiers and in turn he’d butchered the children. It became so much clearer as to why the boy had gone so far when Grant rammed him, the child was hardly five feet tall. All gone, all dead.
Hobbling down the stairs and staggering onto the street, he caught a swaying shadow out of the corner of his eye. Gulping Anderson turned around. A girl hung up by tangled cords which hung from the open window.
It looked like something out of an old movie, like a hanging tree post-witch hunt. Just a kid. He wasn’t at fault, this was war and they were soldiers, soldiers died. Why him though? Out of everyone why did God let him live so he could do this? His rifle clattered onto the street as Grant fell to his knees, and he wept.
I saw the devil today, and he looked a lot like me
What have I done?
And who have I become?