Inspired by Vinnie and Ollie, who actually got me too play Left 4 Dead 2, thanks guys.
The Character names are based on the Fireteam Immortal (Marines) Survivor Pack by MonkeyRebel117

Chapter 1: Just another Sweep and Clean
0800 Hours, March 23, 2526 (Military Calendar) / Gamma 597 System, Orbit around Terros
"BRACE YOURSELF" Dillon's fists clenched as the pelican began to reach terminal velocity, they were expecting heavy fire from Insurrectionists but it was eerily silent. The violent shuddering of the pelican came to a sudden halt as the engines were powered up, the short, quick breathes of the team began to slow down as they began to feel secure again, the pelican slowly approached the landing zone, atop a block of flats, contact with the entire planet had been ceased until a week before the mission a distress call was sent out. Now the cavalry had arrived, 4 of the best marines in the U.N.S.C, Trojan squad. They'd made entire battalions of rebels disappear, but it looked like their work had been cut out for them, the entire city seemed derelict.
"All right cupcakes here's how it goes" the familiar words of Captain M'cory crackled to life through the communication receivers in each head gear. "We got a distress call saying something about a planetary emergency so, we send you down, clear the city for reinforcements and we rescue every civie we find, understood marines?!"
"Sir yes sir!"
The comms cut out and Sgt. Maravilla turned to his comrades "All right Marines you know how it goes sweep and clean" and with that the pelican took off and the marines ventured into the building. The power was off. Dillon's sense of security was rapidly deteriorating, this was0 his first mission in Trojan squad, "What's wrong Dillon, you afraid of the dark?" teased Khan, unlike Dillon, Khan is a seasoned veteran, being a part of Trojan squad for over three years he had survived countless missions and killed countless foes. "Flashlights on people, and Khan, cut your tongue before I cut it for you" said Maravilla. As they progressed through the corridor they came across their first casualty, a woman, maybe in her late 30's was lying on the floor with a good section of her arm missing and her intestines spilled all over the floor. "Gross, bad period huh" said Khan nearly throwing up all over her corpse, "Well I don't know about period but something definitely happened to her" said Swan, "Oh yeah and you would know all about periods, wouldn't ya Swan?" teased Khan, Swan being the only female on the team was often teased in this way by Khan. "Can it both of you, I don't think we're dealing with innies anymore, this is something else" Maravilla turned to Dillon "Contact Light of Retribution, we got an emergency down here" the other squad members looked at each other confused "What's going on Sarge?" asked Dillon, he Battle Rifle raised to a defensive position across his chest, Maravilla turned to face him his breaths short and frantic , his eyes widened with panic "I said get hold of command, what the hells wrong with you soldier", Dillon frantically reached around for his transmitter, "Patching through now sir" Maravilla became for tense, gripping his shotgun so much that he made an imprint "What's going on down there team?" Captain M'cory's gruff voice rang through the transmitter "Why aren't you using the recievers in your helmets?", Maravilla edged towards the transmitter "ONI don't monitor UNSC channels, they mustn't know what has happened down here" Khan walked over to the sergeant "What has happened Sarge?" Maravilla gulped "It's just like what happened like Harvest five years ago, the infection has spread to Terros" there was a long pause until finally "I'm sorry Trojan's, there's nothing we can do for if this is planetary then there's no hope, I'm sorry we can't risk it getting on board the ship, goodbye" and with that the communications shut.

"Let me get this straight, they're leaving us?" Khan said pacing up and down the corridor "There's nothing they can do, we're stuck down here, we may as well give up and let it happen" Maravilla said his head in his hands "Uh let what happen Sir?" Dillon asked still gripping his rifle, "Sarge we got movement, two floors down, approaching fast" shouted Swan, "Sarge what's happening?!"

"The dead have rose again"