Staldra

Gleeoks appear as a common enemy in Skyward Sword. The can be found in the Skyview Temple and the Lanayru Mining Facility. Link must use his sword to cut off all the heads at once, as they will grow back if he doesn't.

Trivia

 * Staldra is a portmanteau of "Stal" and "Hydra". Stal is a prefix used to denote skeletal creatures, such as the Stalfos.
 * Gleeok are similar multi-headed creatures.