Waller

"Hey, I didn't know you made house calls, Foehammer!"

- Sergeant Waller during the Battle of the Silent Cartographer.

Gunnery Sergeant Waller was a non-commissioned officer in the UNSC Marine Corps during the Human-Covenant War. He was in command of an Orbital Drop Shock Trooper unit during the Battle of Installation 04 in September 2552.

Battle of Installation 04
Waller was one of the Marines stationed aboard the as part of Major Antonio Silva's and 1st Lt. Melissa McKay's ODST infantry contingent. He was aboard the Autumn along with the rest of his unit when the ship made the random slipspace jump to Installation 04 after the major defeat at Reach during the battle that took place there.

He was present when the Pillar of Autumn was boarded by the Covenant during the opening phases of the Battle of Installation 04. He successfully escaped the ship, that later crash landed in a desert on the ring.

Presumably, he was part of the attack that took Alpha Base and later part of the convoy McKay made to transport supplies from the Autumn.

The Cartographer
Waller was one of the Marines in charge during the airborne assault on the Cartographer. His squad was successful in securing a beachhead on the island for most of the operation, having fended off at least two additional Covenant attacks as MCPO John-117 proceeded to locate the map room. The Marines took an unknown number of casualties, but among the confirmed deaths were PFC Hosky and an unidentified corporal, who were killed by Hunters while aiding the Master Chief.

Later, the squad was caught in the open when a surprise Covenant assault team bore down on them. Waller urged the Chief to find the Cartographer while his squad fended off the attack, since the Marines were unable to reach the main facility for cover. With dropship Bravo 22 destroyed halfway through the op, Echo 419 escorting the Master Chief on a higher-priority mission, and what remained of the squad in no condition to assist, Waller and his remaining men were either killed or waited on the island for extraction.

Trivia

 * Waller serves as a canonical replacement for the Sergeant Stacker NPC on the Halo: Combat Evolved level The Silent Cartographer.
 * Waller is presumed to have been killed by the Covenant on the island along with his entire squad, as the Marines can be found dead on the beach at the end of the level. However, this could simply be a gameplay mechanic and may not be canon, and it is in fact possible to save up to six Marines in-game.

List of appearances

 * Halo: The Flood