Area 51: The One With The Alien Mutation
Not to be confused with its loosely related follow-up, Blacksite: Area 51, 2005’s Area 51 is a first-person shooter that is itself loosely based on the 1995 arcade light-gun shooter of the same name. Area 51’s gimmick is not its confusing pedigree. Partway through the game protagonist Ethan Cole is infected with an alien mutagen, granting him the ability to temporarily transform into a mutant himself. As a low-key monstrosity, Cole gains increased stamina, the power to easily spot cloaked enemies, health-enhancing parasites he can fire at enemies, and other fun alien stuff.
Ethan’s coolest power, however, was that his voice sounded just like actor David Duchovny, due to his being voiced by actor David Duchovny.