This is DustedPandemonic/Hecatia's Complex Doom addon.
The only requirements are LCA and, of course, Complex Doom.


Credits are listed below.

If credits aren't listed for something, that means that I was 
not able to find an author of the specific item (or I'm just lazy).

Tripwire Interactive: Gore Imp, Cerebral Caco, Cerebral Imp, and Infernal Cybernoble sounds (Killing Floor)
Nakkemake: Old Desolator sprites
Vader: Nether Imp and Terror sphere sprites
Damien Daurio: Gore Imp sprites (edited by Dusted)
Neoworm: Chaos Soul sprites (edited by TiberiumSoul)
Ben2k9: Cyber Baron sprites
Raven Software: Dark Bishop sprites and sounds (Hexen), Legendary Archon sounds (Hexen 2), Chaos Soul, Desolator, Spec Ops Zombie, Overseer, and Hierophant sounds (Quake 4)
id Software: Legendary Vile sounds (Doom 3)
Freedoom: Dark Bishop death sound
Team Shanghai Alice: Spider Masterspark attack sounds (Touhou)
Ghastly_Dragon: Spec Ops Zombie sprites, Code
Xim: Spec Ops Zombie sprites
Vegeta: Spec Ops Zombie sprites
MagicWazard: Spec Ops Zombie and Salvation sphere sprites
Hacx: Unstability sphere sprites
Eriance: Doom Sphere sprites, Plasma Repeater sprites, Explosive Shotgun sprites, Hierophant sprites, Plasma Repeater code, Hierophant code
Relic Entertainment: Former Admiral sounds (Dawn of War)
Lord Cylarne/Ultimate Apocalypse Team: Legendary Necromancer, Legendary Vile, Pain lord, and Overseer sounds (Dawn of War Ultimate Apocalypse mod)
General Roasterock: Legendary Afrit and Lesser Cardinal sprites
Pillowblaster: Code for various effects
P.H.O.B.O.S: Leg Salvation Sphere idle sound
osjclatchford: Hell Staff sprites
Craneo: Explosive Railgun sprites, Tesla Rifle sprites
Arkore: Adding DoomEdNums to all enemies, weapons, and items
Uboa: Occult Spellbook hand sprites
Daedalus: Code
Harbinger: Code
Legendary: Code
Titanium: Code


Music for the enemies that have them:
Legendary Phase Imp "Audiomachine - There Will Be Blood"
True Legendary Zombie "Audiomachine - Lost Raiders"
Bloody Flandre "AGENT 0 - Bloody Law"
Legendary Necromancer "Dark Souls II OST - Royal Rat Authority"
Legendary Vile "Dark Souls OST - Manus, Father of the Abyss"
Legendary Afrit "Dark Souls OST - Black Dragon Kalameet"
Legendary Archon of Hell "Dark Souls OST - Ornstein & Smough"
Sacrosanct Overseer "The Dark Side of Phobos - Iron Cathedral"