MAP20: Breakdown (Doom 64)

One of the most disturbing maps, large portions of Breakdown shift and change completely, disorienting the player and making navigation difficult. The BGM consists of suffering demon moans, the voices of humans ranging from tormented souls and marine communication speak, and fly buzzing. In the Doom 64 TC, a shrine of Scuba Steve can be located. The console version contains an extremely difficult to find secret which only a select few have discovered. An interview on Doom Depot revealed that this level allegedly contains an easter egg involving the red key room that even its creators cannot remember how to activate; however, no player has ever successfully found this secret, and according to Doom 64 TC creator Kaiser, the egg seems to have been removed, with useless fragments of its activation (specifically, a number of mysteriously tagged walls) scattered around the play area.