Yig

Yig, also known as The Father of Serpents or The Snake-God, is a Great Old One which appears in H.P. Lovecraft's Cthulhu Mythos.

Description
Manifesting as a gigantic snake with the arms of a man, or sometimes a reptilian humanoid creature, Yig is considered to be the god of snakes and serpents everywhere. He feels a fierce devotion to his "children," emerging from his sleep every autumn to punish those who harm them. He does this either by turning them into serpents or serpent-like wretches themselves, or simply sending other snakes to kill them when they sleep.

History
In times long passed, Yig and his then-mate Coatlicue ruled the crimson cavern of Yoth beneath the subterranean land of K'n-yan, where the two were worshiped as gods by the denizens of Yoth, the Serpent Men. This arrangement came to an end when the Serpent Men transferred their veneration to Tsathoggua, and mighty Yig placed his curse upon them.

Yig is also thought to be the deity responsible for the legends of the Kukulcan and Quetzalcoatl worshipped by some tribes found deep in earth territory of Sornieth.

Yig is the one whom cursed Medusa into being a snake like demon for eternity for challenging him. Forever cursing her to slither across the earth, have snake as hair and no man can look at her with out turning to stone.

Family
Yig
Mappo no Ryujin, mother
Rokon, brother
Coatlicue, former mate
Ayi'ig, daughter by the Outer Goddess Yidhra
Voltiyig, son
Appearances
The Curse of Yig (1929), by Zealia Bishop and H.P. Lovecraft.
He also appears as an antagonist in Fantasy Flight Games' Arkham Horror board game.