d Software in which you control a lone space marine on a Martian base overrun by the damned.
Entering a code for this game in MechWarrior II causes it to claim "This ain't [this game], bub!" and self-destruct the player's mech. It ends with the prominent image of a decapitated rabbit for which revenge will be taken in the sequel; that sequel, subtitled Hell on Earth, secretly has the head of a programmer on a stick as its final boss. Modifications could be made by .WAD file editors but built-in cheat codes include idspispopd for no clipping and idkfa for all weapons including the chainsaw, rocket launcher, and BFG-9000. Billed as "Wolfenstein on steroids," it would itself be followed by Quake. FTP, name this classic game by id Software in which you control a lone space marine on a Martian base overrun by the damned.
Entering a code for this game in MechWarrior II causes it to claim "This ain't [this game], bub!"
Doom