Doghouse Glitch allows Link to access a corrupted version of the game's underworld and dungeon maps activated by touching a door warp from an unintended direction. This is usually done by touching a door warp (normally entered from below) from above. Collision data for floor tiles, sprite appearances, items within chests, and more are altered when within these maps. This leads to very interesting effects, some of which are helpful in a speedrun. The differences between glitched maps are directly dependent upon your kill counter, normally used to deterine whether the Piece of Power should drop or not. For example, killing three enemies before activating Doghouse Glitch will have different effects than if you kill four enemies.
Below is a video showing how to activate Doghouse Glitch after killing 3 enemies.