Orcus

& Orcus
Difficulty	36
Attacks	Weapon 3d6, claw 3d4, claw 3d4, spell-casting, sting poisonous 2d4

& Orcus
Difficulty	36
Attacks	Weapon 3d6, claw 3d4, claw 3d4, spell-casting, sting poisonous 2d4
Base level	30
Base experience	1421
Speed	9
Base AC	-6
Base MR	85
Alignment	-20 (chaotic)
Frequency (by normal means)	Unique
Genocidable	No
Weight	1500
Nutritional value	500
Size	Huge
Resistances	Fire, poison
Resistances conveyed	None
Orcus: can fly. can see invisible creatures. is poisonous to eat. does not eat. (*) is not a valid polymorphable form. is a demon. is an overlord to its kind. is male. is normally generated hostile. can follow you to other levels. is nasty. can pick up weapons and food. wants the Amulet of Yendor. wants the Book of the Dead. has infravision. can be seen through infravision. appears only in Gehennom. never leaves a corpse.
Reference	monst.c#line2684

Orcus, &, is one of the demon princes, guaranteed to appear in Orcus Town in Gehennom.

Orcus does physical damage and some spell damage, both of which you should be ready for. He also carries a wand of death, although for any character with magic resistance, the main problem this poses is how to relieve him of it without him wasting too many charges (hint: wield a cockatrice corpse or potion of paralysis)

As a chaotic Demon Prince, Orcus can summon Yeenoghu and Demogorgon.

Encyclopaedia entry

Orcus, Prince of the Undead, has a ram's head and a poison
stinger. He is most feared, though, for his powerful magic
abilities. His wand causes death to those he chooses.