In the roguelike game Nethack, wizard mode (also known as debug mode) grants a character a number of powers not available in the normal game. These include: unlimited wishes (even for dungeon features, not necessarily items), level teleports, and item identify; the "Die? (y/n)" prompt found also in Explore Mode; the option to force the creation of a bones file; dodging of the no-restore-after-death feature. Uses for this are numerous: finding new YAFM and ways that The Devteam Thinks of Everything, reproducing bugs, or ascending with a wholly invincible character, for instance. An ascension can be achieved within two game turns in wizard mode.

Accessing this mode varies from system to system. In the Macintosh version, entering debug mode is an option at the character creation screen. In DOS, typing "nethack -D -uwizard" will begin the game in debug mode.