Phelios is an 8-bit side-scrolling action game developed and published by Sega for the Genesis home console. The game is a port of the arcade game Phelios, and was released in Japan on December 3, 1989. It was later released in North America and Europe on December 9, 1990. Phelios is an action-adventure game set in the ancient world of Phelios. The player controls a character named Poseidon, who must guide the ship through dangerous waters to safety. The game features an unique control scheme which allows the player to use both hands to move the character around. The game is set in a large open world, and has several different areas to explore. The player can also collect various items to improve Poseidon's abilities, and use them to defeat enemies.