Helmasaur King

Helmasaur King was the boss of the Palace of Darkness in The Legend of Zelda: A Link to the Past. He was a reddish, four-legged beast, complete with a durable iron mask and a long, spiked tail which he would use to strike Link. Link eventually defeated the creature by weakening and ultimately destroying his mask; he then fired arrows at a green jewel which became visible on his forehead. After the battle, Link recovered a magical Crystal needed to unlock the entrance at Ganon's Tower.