Episodes and levels of DOOM

The computer game Doom consists of 36 levels in four nine-level episodes: Knee-Deep in the Dead, The Shores of Hell, Inferno and Thy Flesh Consumed (Thy Flesh Consumed was added in the upgrade Ultimate Doom). Levels 1-7 in each episode are regular levels, while number 8 is a boss battle; the ninth is a secret level that can be accessed from within one of the first seven. The levels are referred to as ExMy (episode x, mission y), but also have individual titles.

For information about the levels in Doom II and Final Doom, refer to those articles. For differences between the PC version and its various ports, refer to Doom versions and ports.

Trivia
The version of E1M4 in Doom 1.0 contained a structure that formed a swastika (visible in the upper-left center of the 1.0 map to the right), inserted as homage to Wolfenstein 3D (which was set in a Nazi base and had several swastika-shaped levels). The symbol was changed to a shape that only loosely resembles a swastika for version 1.4:


 * "Yes, [in Commander Keen 5] there is a swastika in one of the levels, one of my levels to be exact, but I removed it shortly after the game was released because people were upset that an evil symbol was in a cute kid's game (the changed version is in the screenshot). It was a premonition of things to come, namely, Wolfenstein 3D. I also put a swastika in Doom ' s E1M4 as a Wolf3D reference, but I changed it later for the exact same reason."undefined

– John Romero

One of the levels in the original three episodes that was changed for The Ultimate Doom is E1M1. The change consists of the addition of a hidden switch near the start of the level that opens a door to the courtyard. The revised E1M1 contains exactly 666 sidedefs. The other changed level in The Ultimate Doom is E1M8. The change consists of a hidden switch behind a wall in the right chamber of where the Barons of Hell come out. This switch allows you to return to earlier sections to get more ammo.

The band Lollipop Lust Kill wrote a song titled "Knee Deep in the Dead" paying homage to the game.

Trivia
In E2M9, after 26 seconds playtime the song sounds almost exactly as Pantera's song "Mouth for War" from their album Vulgar Display of Power which was released in 1992.

Trivia

 * E4M1 contains a representation of the Nine Inch Nails logo.
 * All the level names (except E4M9), and the episode title, are phrases taken directly from the KJV of the Bible. The list was compiled by Kevin Cloud, and John Romero assigned names to the individual levels.
 * E4M2 is the level of all those John Romero contributed to DOOM and DOOM II that took him the shortest time to finish; he started working on it at midnight and was done 6 AM.