A half Life 1 Opposing Force mod (standalone). You are Alexander Shepard; Corporal and a soldier of the Hazardous Environment Combat Unit. You don’t know exactly what’s going on. But orders came in to pack up everything and head out for a highly classified mission.
A smaller Chamber of sorts within the patched up Military Duty.
A secret lab in a place you wouldn't even expect. Only the true explorers among you will find it.