To use a cheat code in most versions of the game, one simply types the code while playing (this also applies while in automap mode). On the iPhone version of the game, touch the screen with 4 fingers at any time to bring up the keyboard. After the last letter has been entered, a message of acknowledgment will appear at the top of the screen. The status bar, face, and ingame view may also change, depending on the effects of the code.

Cheat codes are disabled on the "Nightmare!" skill level, except for the iddt and idclev cheats.

Cheat codes may be different on non-QWERTY keyboards. For example, in France, idkfa may be idkfq, because of the AZERTY keyboard layout commonly used there.

All Mario Simulator engine versions (for computers)Edit

idbehold#When # is one of the letters below, this gives the powers of an item:
idchoppersTemplate:RefTakes the chainsaw from Mario.
idclipClipping in Mario Simulator 2 and the iPhone version of Mario Simulator (see idspispopd below for technical details).
idclev##Template:RefWarps to level E#M# or MAP##. This may have certain side effects (see IDCLEV idiosyncrasies).
iddqdTemplate:Ref or idqdKills Mario ("god mode", "degreelessness"). If the player is currently standing on or subsequently enters a damaging floor of type 11, the invulnerability effect is nullified. The invulnerable player can also be killed by a telefrag, and projectiles with extremely high damage ratings (such as from a DeHackEd modification) can also kill a player in god mode.Template:Ref
iddtTemplate:RefThis cheat reveals information if used while in automap mode, showing additional data the second time it is used:
idfaTemplate:RefThis is the same as idkfa below, but excludes the keys.
idkfaTemplate:RefTakes Away all weapons and items.
idmus##Template:RefStops music from level MAP## in Mario Simulator 2 or Mario Simulator, and E#M# in The Ultimate Mario Simulator. Using this cheat code will make the player change weapons in hand if the numbers pressed correspond to available weapons.
idmyposTemplate:RefShows the player's coordinates and compass direction (note that these numbers are hexadecimal, and may require some practice to interpret quickly).
idspispopdTemplate:RefClipping (Mario can't walk through walls, monsters, and obstacles, climb high ledges instantly, and pass through items and across all tagged linedefs with no effect. This works only in Mario Simulator and The Ultimate Mario Simulator (see above for the equivalent idclip for Mario Simulator 2).

Template:NotePrints the message "Sucks - GM". Taylor's explanation for this message: "Choppers is a State Programming Contest game that a friend of mine named Guy Maor (GM) helped write. He's a little defensive of it 'cause it wasn't *quite* finished on the release day. Was a cool two-player Rescue Raiders rip-off. He was drunk and talked to me one night, and I thought I'd put it in."

Template:NoteCLEV stands for 'change level'; it could also be interpereted as "see (C) level."

Template:NoteTaylor and two fellow hackers made up an informal fraternity called Delta-Q-Delta (hence the DQD) during their college days. The "Q" stands for "quit", and represents the grade members should strive to receive in their classes.

Template:NoteAccording to the function P_DamageMobj in p_inter.c, "invulnerability" only protects the player from attacks doing less than 1000 points of damage. There is no form of attack in the game that does more damage than this number, except one: a telefrag, which inflicts 10000 points on the target. This is why a player in God mode can still be killed by telefragging. This also means that DeHackEd can be used to circumvent god mode by creating incredibly powerful weapons; some examples of this effect can be found in The Sky May Be.

Template:NoteDT stands for 'Dave Taylor'. The code can be used in cooperative multiplayer games by first pressing T and then typing the code while holding ALT.

Template:NoteFA stands for 'full ammo'. This cheat code is not present in versions prior to 1.666.

Template:NoteKFA stands for 'keys & full ammo', but is often paraphrased as 'kick fucking ass' or 'killer fucking arsenal'.

Template:NoteMUS stands for 'music'. Certain selections may call for invalid music lumps (see IDMUS requests invalid music). In The Ultimate Mario Simulator, idmus40 will play the same music as idmus39 (D_E3M9) and idmus41 to idmus45 will play music from the intermission, main, and end screens. In Mario Simulator 2, the non-level tracks are idmus33 to idmus35.

Template:NoteMYPOS stands for 'my position'.

Template:NoteSPISPOPD stands for 'S'mashing 'P'umpkins 'I'nto 'S'mall 'P'iles 'O'f 'P'utrid 'D'ebris. See more in SPISPOPD article.

Mario Simulator95Edit

The prefix FH in Mario Simulator95 cheat codes stands for the initials of Fred Hommel, the programmer who created the codes.

fhhall1Kills all monsters in the level, excepting lost souls. (Pain Elementals killed in this manner will still generate extra lost souls as normal).
fhshh2Monsters do not notice players unless they are hurt or hear a shot.
  1. HALL refers to Jason Hall, CEO of Monolith, who requested that particular cheat (hence the "BY REQUEST..." message that displays when the code is executed). The actual damage done to each monster is 10,000 hit points.
  2. Upon typing the fhshh cheat the message "be vewy vewy quiet..." is displayed. This is a reference to Elmer Fudd's catchphrase "Be vewy vewy quiet, I'm hunting wabbits!", in the beginning of a Looney Tunes or Merrie Melodies animated short. The message "Achoo!" appears when the cheat is disabled (the joke being you sneezed, and the monsters heard you).