10 Most Famous Video Game Cheat Codes
2. Id Codes - Doom (1993)
You can't play Doom without trying out its legendary cheats at least once. The term 'God Mode', used to describe permanent and unconditional invulnerability of your player character, is often traced back to id Software's first games, and even to this day, the Doom Marine rocks the look way better than most.
The code in question is IDDQD, which you can type in freely at any point in the game to rid yourself of that dreadful inconvenience your enemies know as 'death'. Doomguy's eyes will glow an unblinking, pupil-less gold from that point on, signalling clearly to all that stand before you that Hell ain't got nothing on you and your trusty shotgun.
Another equally popular code is IDKFA, which furnishes you with all of the game's weapons (including the BFG) as well as full health and ammo for everything. It also gives you every key card in the level, so if exploration is encroaching on your killing spree, you're now free to skip all that and go back to ripping and tearing like a good little badass.
Lord help us all if the modern-day Doom Slayer gets his hands on these codes...