The Prophet of Sseratus is a giant former Drakkari troll. According to the quests around the Altar of Sseratus, he and other Drakkari killed the loa god Sseratus and drank his blood. The Prophet seems to have the greatest effect from this.
Hexxer Ubungo wants him slain for the quest  .
- Drink deep my brothers!
- The mojo of Sseratus is ours. Now all will be crushed under the might of the Darkkari!
- I will destroy the Argent Crusade! I will crush the Scourge!
- They dare attack us? The fools! Do they not know we are now all-powerful?!
- Kill these invaders who dare to defile our altar!
- Finish them and then we will move south to kill their brethren!
- I see you, insect! Come closer.