Stealth monsters

Stealth monsters are variants of the Doom and Doom II monsters (spectre excepted) created by Andy Baker (from DOSDoom) and proposed to source port maintainers in 1998. They have been adopted by some ports, sometimes only for a short while: "Proff" Schulze, for example, disabled them in PrBoom two days after having added them, because they introduced compatibility problems with Boom savegames. (source)

The original pack created by Andy Baker is no longer available, not even on the Internet archive.

Stealth monsters are fully invisible (not "fuzzy" like the spectre) except when they attack, are hurt, or die. The monsters are attributed editor numbers by alphabetical order:
 * 9050 	Arachnotron
 * 9051 	Arch-vile
 * 9052 	Baron of Hell
 * 9053 	Cacodemon
 * 9054 	Chaingun guy
 * 9055 	Demon
 * 9056 	Hell knight
 * 9057 	Imp
 * 9058 	Mancubus
 * 9059 	Revenant
 * 9060 	Shotgun guy
 * 9061 	Zombieman

Ports with stealth monsters

 * GZDoom
 * Risen3D
 * Zandronum