The Circle of Four walked many strange roads and not all of them stayed to this world. On the lunar surface they encountered and brought back a spirit of alien resonance. Destroying it was seen as too dangerous at the time as it seemed the being was bound up with the creation of life itself.
So they trapped it in the form of an ancient eternally dead creature, the Antediluvian. Over the eons the two grew into each other until they were one. Now it wants to belong to a group and forms societies to worship and adore it.
It recently joined with Mammon.