u/EXCAVATIONGoldSrcMod

This is from the Aliens vs. Predator 2 single-player demo. No cheats are used (they don’t exist for the demo).

In this mission, you arrive in an APC with two marines who normally accompany you outside. These marines are supposed to disappear when certain scripted sequences are triggered, specifically an early runner alien encounter.

I skipped that scripted encounter by climbing overhead cables. Because of that, the trigger that normally removes the marines never activated, so they remained outside the APC.

I continued to the hive and back while being chased by aliens, again using the cables to avoid triggering the event on return.

The result was interesting. The right marine did nothing during the entire encounter. The other one actively engaged incoming aliens, defending me. Eventually, the inactive marine was killed (possibly by the APC turret). The remaining marine continued fighting for a while, then suddenly turned away and became inactive, which was kind of funny. After that, aliens stopped targeting him and focused solely on me instead.

Finally, I approached the APC to trigger the mission cutscene, and the vehicle drove straight through the remaining marine. I’ll try it a few more times as I'm curious if it’s possible for both marines to be killed.