Demon of the Frenzied Blood
Alignment: Chaotic Evil
Color Type: Red - Strong Named Enemy
Attack: Slam (Bludgeoning), Spellcasting (Chaotic Spells)
Description: Demon of the Frenzied Blood is an optional red named hezrou encountered in Into the Deep. You can destroy him either before or after the quest is complete, though the storyline recommends doing so after. And that is also required on epic difficulty as you would otherwise not be able to loot the epic chest he holds if the quest was not complete. He has a massive amount of hitpoints and is very challenging. The tar like sludge he is standing in damages party members and heals him. He opens Unstable Portals that summon Fire Reavers, a very strong caster can kill all the portals before they can summon any fire reavers. A decent caster can at least keep the reavers occupied while the party takes on the Demon.
When the party is overwhelmed, pick up stones and dimension door to the entrance (don't leave the quest). You can shrine up there and return to the fight; hezrou will not regenerate much but the portals/reavers will be gone (for a while).