Magtail

The Magtail is a lava-tolerant centipede monster that resides in the superheated, volcanic regions about the Great Sea in The Wind Waker. It slithers around rooms, waiting for helpless prey to come close. Upon recognizing a threat, it will stretch out its mandibles, and then slice them down upon the helpless victim. However, direct exposure to the eye of the creature by a variety of weapons such as the Grappling Hook causes the creature to curl into a hardened ball. The Magtail, in its stiffened form, can be used to depress switches or the Magtail itself could be killed, if desired. Water could also be used to force them into a tight, hard spiral; the same effect can be achieved through the use of an Ice Arrow, as well. Magtails take quite a few hits to destroy, considering their strong, natural armor.

Trivia

 * If Link needed to dispatch of a Magtail quickly, doing a downward thrust through the Magtail's head, through use of Link's parry ability would be sufficient.