Ryūjin (Japanese 龍神 "dragon god", also called Rinjin and Owatatsumi) was the god of the sea in Japanese mythology. He was a dragon, a symbol of the power of the ocean, had a very big mouth, and could transform into human shape. Ryūjin lived in Ryūgū-jō, his palace under the sea built out of red and white coral, from where he was believed to control the tides with magical "tide jewels". Sea turtles, fish and jellyfish were Ryūjin's servants.