C'thulu

C'thulu is a Great Old One.

The precise origins of the Old Ones is somewhat uncertain. It has been suggested they are the corpses of the First Gods, or perhaps those who were driven insane or injured by the Oan superweapons in their eternal war against the Celestials.

Most of the Old Ones dwell in Nullspace, caught in a state of fitful slumber spanning aeons. It has been suggested that the Endless had a role in locking them away behind the universe, particularly the Dreamlord.

C'thulu was summoned by Morgan le Fay in 15,000 BCE, when Atlantis was threatened by the Celestials. The presence of a Great Old One required using the last power of the Demiurge to lock it away, dooming the entire city of R'lyeh to drown as the oceans rose and mountains fell.

It slumbers still, trapped eternally in a pocket demesne and guarded by The Black.