What ale's you my friend?
So, you wish to learn about the creatures that are in the cd, but not in the game, well, the main thing that I can tell you is, that the only way to get these creatures out of the cd and into the game is to get a trainer at raymon tan's page, which is in the links page, I would be care full though, they are harder than the creatures that you normaly find in hell.
Here they are, the hidden creatures
The Arch-lich Malignus
Hit points = 160, Resists Magic fire lightning immune none
(couldn't get nightmare/hell info, cept getting ilegle opperations, but on hell is immune to all)
Bone demon
Normal: Hit points = 70, Resists none, immune magic
Nightmare: hit points = 310, resists none, immune magic
Hell: hit points = 480, resists none, immune magic
Devil kin brute
Normal: Hit points = 160, resists none, immune none
Nightmare: Hit points = 580-760, resists none immune none
Hell: hit points = 840-1080, resists none immune none
Incinerator
Normal: Hit points = 30-45, resists none, immune magic fire
Nightmare: hit points = 190-235, resists none immune magic fire
Hell: hit points = 320-380, resists none, immune magic fire
invisible lord
normal: hit points = 278, resists all, immune none
Nightmare: hit points = 934, resists all, immune none
Hell: hit points = 1312, resists all, immune none
Lord sayter
Normal: Hit points = 351, resists magic fire, immune none
Nightmare: hit points = 1153, resists magic fire, immune none
Hell: hit points = 1604, resists magic fire, immune none
UNraveler
(My trainer never lets me use this guy, but if yours does, please kill him 30 times and get me his info.)