The sixth mission of Halo: Combat Evolved still haunts me today.

Players are tasked with adapting to Covenant tactics throughout the first five chapters of the game. This pantheon of alien races presents a host of problems in every firefight. Eliminate the Elites first, flank the Jackals, and finish off the remaining Grunts. I spend hours learning how best to deal with each situation. A few well-placed grenades here or a quick melee attack there and I’m moving on to the next encounter.

In the mission 343 Guilty Spark, however, things become a little more complicated. As the Master Chief, I’m traveling the halls of another Forerunner construct. I approach an unlocked door, and the hairs on the back of my neck stand up. Screeching violins escalate in volume as I hear a strange noise echoing throughout the corridors. The door slides open and a marine collapses into the Chief’s arms. I expect Covenant on the other side, but there is only silence. A UNSC helmet rests on the floor amidst a drying pool of blood. The Chief removes the helmet’s video chip, and plays back the dead soldier’s recording. This removed perspective doesn’t alleviate the eerie atmosphere. 

At first, the footage seems normal. The mission seems to be going fine as the marines approach the construct. But the following scene is what chills me. What could have torn this Elite’s chest apart like that? Is it still here? My hands are shaking, and I can’t hold the controller tight enough.

The next clip is chaos. As the Flood pour in from every angle, I’m desperately waiting to regain control of the Master Chief. As the cutscene ends, the fact that I’m standing right where the previous footage took place drives home the sense of paranoia even more.

The introduction of the parasitic Flood creates new dilemmas for combat situations throughout the rest of the game. Whereas fighting the Covenant requires traditional shoot and cover tactics, combat against the Flood seems more tailored for a zombie game. The mission 343 Guilty Spark still stands out as one of the most terrifying levels in any shooter I’ve played.