Morpha

Morpha, the Giant Aquatic Amoeba is the Boss of the Water Temple in Ocarina of Time, and has complete control over the water in the room in which it resides. It creates long water 'arms'. It will try to catch Link in these arms, and if it succeeds, it'll put the squeeze on him. For Link to defeat this fiend, he must take out his Longshot, pull the amoeba towards him, and slash it. After defeating it, Link will recieve a Heart Container and the Water Medallion.