The Ultimate Doom

Ultimate Doom is an upgraded version of Doom released on April 30, 1995, adding the fourth episode Thy Flesh Consumed. Those who already owned Doom could download a patch that upgraded their copy to Ultimate Doom. The following changes were also made to the game:


 * the addition of a few passages in E1M1: Hangar
 * a secret switch in E1M8: Phobos Anomaly
 * sector type 17 from Doom II
 * several new linedef actions, including fast raising doors and keycard switches
 * the behaviour of A_BossDeath was altered, breaking the PWAD Doomsday of UAC

The level changes were added to allow for a more interconnected deathmatch play.