Rhogog is a Great Old One from the Cthulhu Mythos. Known as "the Bearer of the Cup of the Blood of the Ancients," Rhogog is said to be a being of darkness, and most often manifests as a huge, leafless tree with a staring eye in its trunk.

Rhogog was created when Cthulhu and Hastur clashed over Britain. The blood of Cthulhu that fell on the land was tampered with by his Star Spawn, and eventually mutated into the the Great Old One Rhogog.

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