Doom · PC · 1993 · Cheat Code
Effect: Gives the player all weapons, full ammunition, all keys, and full armour.
IDKFA — which id Software staff jokingly expanded to "ID Keys, Full Ammo" — was one of the original cheat codes shipped with Doom and quickly became the go-to shortcut for players who wanted to experience combat with the full arsenal from the start. An earlier version of the code, IDFA, provided all weapons and ammo but no keys, making IDKFA the more complete variant. Together with IDDQD, these two codes defined the cheat-code culture of 1990s PC gaming and were memorised by a generation of players.