Doomsday of UAC



Doomsday of UAC (commonly known by its filename UAC_DEAD) was released in 1994 as one of the first fan-made PWADs. It was considered one of the top 100 Wads of All Time by doomworld as part of their 10 years of doom celebration.

UAC_DEAD features an attempt at creating releastic looking vehicles and environments. It has a replacement sky texture (taken from nightfal.wad) and the first use of the self-referencing sectors trick, used to simulate both invisible stairs in the style of the film Indiana Jones and the Last Crusade and an invisible chamber enclosing a cyberdemon. Careful Flat/Textures choices are used in places to simulate coloured lighting.

Bugs
The map occupied the E1M8 slot in order to use the special tag 666 twice, exploiting a peculiarity of doom's handling when more than one boss monster is present in the map. This peculiarity was changed at some point since 1994, rendering this map un-playable with modern source ports.