The items needed to obtain the Regal Ring are the Whirlwind, Boomerang, Bombs, and the Whip. Link cannot use his sword or bow in the dungeon. The dungeon can be played an unlimited amount of times, allowing Link to obtain as many Regal Rings as he wants. A Treasure Chest can also be found on the island by playing the "Song of Discovery" at the point where the two lights from light crystals intersect, activated by playing the "Song of Light".