Cercyon

Cercyon ("boar's tail") is a figure in Greek mythology. Poseidon had sex with Alope, his grandaughter through Cercyon, begetting Hippothoon. Cercyon had his daughter buried alive but Poseidon turned her into the spring, Alope, near Eleusis.

Cercyon was the King of Eleusis, and a very strong man. He stood on the roads around Eleusis and challenged passers-by to a wrestling match. The loser (always the passer-by) was murdered, though Cercyon promised his kingdom to anyone who won. He was eventually beaten and killed by Theseus, who took the kingdom of Eleusis.