The Beyonder is the most powerful being of the mainstream universe. The Beyonder was also a mutant. Exposure of his mutant genes to Terrigen Mists had created an unprecedented reaction, bestowing upon him seemingly godlike abilities and granted him amazing power and knowledge beyond all other Inhumans of his time, and also erased for an unknown reason him from Black Bolt and the Inhumans' memories.

http://marvel.wikia.com/Beyonder_(Earth-616)