Black beasts are demonic beasts formed from someone using a hero's relic without a crest. Black beasts don't seem to have intelligence and attack everyone on sight. The most famous appearance of a black beast was the Conand Tower indecent, When Micklan Guatier (who was born without a crest) stole the Guatier relic, the lance of ruin, and tried to use it at Conand tower. He became a black beast and rampaged throughout the tower, killing most of the thieves he had brought with him.