Skull Hammer

The Skull Hammer is found upon returning to the Forsaken Fortress and defeating Phantom Ganon in The Wind Waker. It is used for hitting switches and enemies. When used it causes shockwaves which can stun nearby enemies. It can also be swung sideways to knock enemies for six, and can be used as a shield.

This is the key to defeating the Helmaroc King. Link must use it to break apart the Helmaroc King's helmet before he can slash at its vulnerable head.

Other hammers

 * Hammer from The Adventure of Link
 * Magic Hammer from several Zelda games
 * Megaton Hammer from Ocarina of Time

Trivia

 * The Skull Hammer has some humorous effects when used on Miniblins. If Link hits a Miniblin with the vertical attack, it will flatten. If he hits with a horizontal attack, the Miniblin will fly a long distance in the air, and explode. If he hits the ground near a Miniblin, it will fly high in the air, and comes down after a few seconds, still alive.