IDDQ

iddq refers to a well-known cheat code from the 1993 first-person shooter Doom by id Software. The sequence, commonly written as IDDQD (case-insensitive in most ports), activates God mode, providing invulnerability to damage and effectively allowing the player to move through the game without taking hits. The term iddq has entered gaming vocabulary as a shorthand for invulnerability or “God mode.”

Origin and naming

The cheat code was built into Doom’s original password-protected cheat system and is one of the era’s most famous examples of in-game console cheats. A widely cited explanation for the acronym is that IDDQD stands for “Id Software’s Doom God mode,” though the developers have not published an official backronym. The concept of entering a code during play to alter rules of the game emerged as part of Doom’s early cheat culture and quickly spread to later id Software titles and fan communities.

Gameplay and effect

When activated, IDDQD grants the player immunity from most damage, allowing uninterrupted exploration and combat with enemies. It does not, in some ports, alter other gameplay systems such as weapon behavior beyond invulnerability; in practice, the effect is to prevent death from enemy attacks. Players can toggle the effect on and off by re-entering the code.

Legacy and cultural impact

IDDQD became emblematic of cheat codes in early PC gaming and influenced the wider gaming culture around hidden features and debugging shortcuts. It is often cited alongside related cheats like IDKFA (all weapons and items) and IDCLIP (noclip). The term remains a reference point in Doom lore and is used more generally as a shorthand for invulnerability or “God mode” in discussions of classic games.