Moldorm

Moldorm in A Link to the Past
Moldorm makes it's home inside the Tower of Hera and guards the Pendant of Wisdom, the third and final pendant Link must collect. Moldorm is easy to defeat, as six swings of your sword to the tail of the beast with rid the Tower of Moldorm. However, each swing makes Moldorm go faster. Also, he is situated on a platform, high atop the Tower. If Link is knock off the platform, he plummets to the floor below, and must restart the battle. For winning, Link gains the Pendant of Wisdom, and access to the Legendary Blade: The Master Sword

Moldorm in Link's Awakening
Moldorm also is the final boss of the Tail Cave during the adventure in Link's Awakening. He guards the Full Moon Cello, one of the Eight Instruments of the Siren that Link must collect to awaken the Wind Fish on Koholint Island. He is defeated the same way as in A Link to the Past, by striking it's tail, without falling off the platform. However, you must only strike the tail 4 times instead of 6.