Doom Bible

The Doom Bible is the original design document for Doom, written by Tom Hall.

Some bits and pieces from the Doom Bible show up in various places:
 * The prefixes TROO, SARG, and BRS on IWAD lumps for the Imp, Demon, and Baron of Hell come from their Doom Bible names: Demon Trooper, Demon Sergeant, and Bruiser Brothers.
 * The Unmaker appeared in Doom 64.
 * Of all the proposed episode names, only Knee-Deep in the Dead made it into the final game. It was originally to be the third episode of six.
 * The game originally took place on a planet called Tei Tenga. If you look closely at some of the computer panels in Doom, you will see that they still say "UAC BASE TEI TENGA" on them.
 * The game Terminal Velocity also featured a planet called Tei Tenga.
 * All of the playable characters in the game Rise of the Triad had origins in the Doom Bible. Some had their names altered, and one only appeared as a possible name, but one or two were unchanged from their original descriptions.
 * In Strife, there is a place where the player must use a severed hand to unlock a door. This was also proposed in the Doom Bible.  (Some observers believe this to be a coincidence.)