doom_e1m8b

Doom cheats are typed straight into the running game — there is no console and no menu to open. You simply type the code on the keyboard while running through a level, and a confirmation message appears at the top of the screen after the last letter. If you are playing in the browser, click inside the game window first so the keyboard talks to the game and not to the page. This is a first-generation Doom game, so noclip is IDSPISPOPD and IDCLEV takes an episode plus a map — IDCLEV41 sends you to episode four, map one. This is the same Romero map as the entry with the long title: it replaces E1M8, so IDCLEV18 takes you there.

For a single map, IDDT makes the most sense — the automap shows you the whole floor plan at once and you immediately see how it was built. Doom cheats are not hidden in a menu, they are simply key sequences — which is why you can trigger one by accident. They are also worth saving for a second playthrough: IDDQD turns Doom into a shooting gallery and switches off the rule the whole game is built on, namely managing ammo and health.