The Twelve Kingdoms Season 4 Episode 4

The God of the Sea in the East, the Mighty Ocean in the West - Final Chapter

Atsuya loses support from his people when the people rebel against Atsuya's army for attempting to destroy the dam that the king had ordered his men to built. Later face to face with the King of En, Atsuya is given a choice to either surrender or to take the throne by a one to one sword battle.