Demon
Demon can be found in the following locations: Hero Cave, Ferumbras' Citadel, Goroma, Ghostlands Warlock area unreachable, Liberty Bay hidden underground passage unreachable, Razachai, deep in Pits of Inferno (found in every throneroom except Verminor's), deep Formorgar Mines, Demon Forge, Alchemist Quarter, Magician Quarter, Chyllfroest, Oramond Dungeon, Abandoned Sewers, Hell Hub and Halls of Ascension.
Demon has 8200 hitpoints. It is immune to fire, life drain, and drowning damage. It is strong against physical, energy, earth, and death damage. It is weak against ice and holy damage. It can neither be summoned nor convinced.
Demon yields 6000 base experience points. Its loot can include purple tome, gold coin, small emerald, small amethyst, small ruby, small topaz, red gem, demonic essence, talon, platinum coin, might ring, stealth ring, platinum amulet, orb, gold ring, ring of healing, giant sword, ice rapier, golden sickle, fire axe, devil helmet, golden legs, magic plate armor, mastermind shield, demon shield, fire mushroom, demon horn, assassin star, demonrage sword, demon trophy, great mana potion, ultimate health potion, and great spirit potion.