Paranoid Marine

The Crazed AWOL Marine was a UNSC Marine, originally a member of Fire Team Charlie, deployed to what was thought to be a Covenant weapons cache. In reality, the fire team was headed for a Flood Containment Facility.

He was inserted into the swamp by a Pelican, along with Staff Sergeant Avery Johnson, Privates Bisenti and Mendoza, and PFC Wallace A. Jenkins. The squad met up with Captain Jacob Keyes, along with Privates Kappus and Riley, after discovering the remains of a dead Elite. After entering a large hall, the squad was ambushed and attacked by "small, squid-like creatures". This Marine witnessed the death of almost his entire unit, and fled the battle, hiding from the Flood.

Long after the Flood had finished their massacre of Marines and Covenant alike, Spartan-117 came across this Marine. The soldier was a wreck, firing at anything that moved with his M6D pistol, and hollering about "monsters." In Halo: The Flood, it is said that the Master Chief told him to leave the building, but the Marine ignored him, and crawled into a fetal position, whimpered, then fell silent. He also told the Chief to "find your own hiding place!" and claims to be able to "hear them" when the Chief approached. It is unknown what happened to the Marine after the encounter, though most likely he was killed by the Flood. It has also been rumored that he committed suicide.

Lines

 * "Stay back! Stay back, you're not turning me into one of those things!"
 * "I'll blow your brains out! Get away from me!"
 * "Gaaaaahh! Aaaaahh! Don't touch me, you freaks, I won't be like you, I'll die first!"
 * "Find your own hiding place, the monsters are everywhere!"
 * "Play dead! That's what I did... played dead. They took the live ones... Oh, God, I can still hear them!"
 * (sob) "Monsters..."
 * "Ahhhhhh! Ahhhhaaahhh..."
 * "Just leave me alone!"
 * "Sarge? Mendoza? Bisenti? Oh, God... the things took them, oh God, I can still hear them... "(mumbles and cries) "They're gone! Get it? Gone!"
 * "They won't get me! Oh God... oh God I don't want to be like them, please, please no, nooo..."

Trivia

 * His fate is unknown, as the room he was in locks after the Chief comes back out. However, it is possible he proceeded to the structure's "basement", as later a human body is found on a flaming platform, and a pistol lies next to it.
 * There was an idea for the Crazed Marine earlier in the development of 343 Guilty Spark (Level). He would've stayed alive initially, but when the player walked a distance away from him, there was supposed to be a loud bang. If the player returned, they would find him dead on the floor. This was revealed by Joseph Staten on the Halo 3 Legendary Edition bonus disk.
 * As a homage to this Marine in Halo: Combat Evolved, the Halo 3 Suicidal Marine is voiced by the same person, and features similar mannerisms to the original. He can be seen on the level, Floodgate.
 * In Halo: The Flood, Master Chief was actually shot by the Crazed Marine, but he immediately took the M6D from the Marine and tried to talk sense into him before he crawled back into a fetal position.
 * He can be killed with one shot by any weapon.
 * Reloading sounds can be heard, but he doesn't appear to be reloading his pistol.
 * You may hear him shooting after you leave him (but staying in the same room).
 * The AWOL Marine is an example of an Ambient A.I.
 * The Marine does not register on the Chief's HUD reticule as an enemy as it does not turn red; it simply remains blue. Some players still dub him as a Human enemy.
 * He is the only Marine (excluding the Crew Members) in the whole game to use a Pistol, while Pistols are found near dead Marines as well.
 * You cannot move his body after he is killed, even with grenades.
 * Even if you go behind the wall he is sitting against, he seems to be able to see you.