Wolfenstein 3D

E2M8 is impossible to complete with 100% in all categories, due to there being a push-wall maze on the maps that was intended to be part of a contest, which required a sign to be found saying "Call Apogee Say 'Aardwolf'". However, the contest was aborted when the game came out, but the sign was left in. In hindsight, the developers said that they should've removed the sign before release, because they were flooded with calls and mails by players asking what it was about. In later versions, it was replaced with a standard prop from the game.

Although Wolfenstein 3D takes place during World War 2, the enemy soldier getting knocked down by B.J. Blazkowicz on the box cover of the game, is carrying an M16. That weapon didn't exist until 1960.

Voluntarily rated PC-13

The Apple, 3DO, and Jaguar versions all featured improved sound effects and music, and high-resolution graphics. Most notably, the Apple and PC version had different introduction and end level screens. The 3DO and Jaguar versions featured weapon sprites from Doom (1993) and Doom II: Hell on Earth (1994), respectively.