Helmaroc King

In The Wind Waker
The Helmaroc King is a monstrous bird that was manipulated by the evil Ganon. The bird was made to do the deeds for Ganon, one of which was to soar the skies and search the many islands for young girls with pointy ears(A Hylian trait) and then kidnap them. The very same bird is responsible for the kidnapping of Link's sister, Aryll. This bird wears a protective stone mask which requires a heavy weapon to destroy. This bird is the boss of Links second trip to the Forsaken Fortress.

~Strategy~

At the beginning of this fight for vengeance, the Helmaroc King will flood the tower and follow Link as he runs along the wall to avoid the rising water. Right now, do the best you can to avoid the bird and the enemies along the steps of the wall. Just keep running until you get near the very top, where the bird will swoop down and stand right in your way. Take out the Skull Hammer and give it a good smack right in the face. It will scream and fall into the rising water, giving you the chance to climb out of the flooding tower. At this point, the floor of the tower will begin to close and the bird will fly up out of the tower to challenge you. This is where the battle really begins.

The Helmaroc King will perform three attacks. The first of these is where it lands on the ground, walks toward you, and attempts to smash you with it's beak. If it misses you, the beak will get stuck in the floor. This will give you the chance to get out the Hammer and smash it on the helmet. This will produce a large crack on the helmet, evidence of the damage you are doing. (This is the move you want to wait for to deal damage.)

It's other two moves are: 1.) Flying around the tower and trying to run you over by scratching it's claws on the floor. 2.) Floating in the air and flapping it's wings in an attempt to blow you into the spikes surrounding the arena.

After you hit it on the helmet with the hammer three times, it will crack and fall off. Now the bird knows it's in trouble, and it will become much more frantic. Once again, wait until it tries to peck you with it's beak. While it's stuck in the floor, draw the Master Sword and slash it in the face. After two or three times of this, the bird will display it's death sequence by flying up into the air and exploding into purple dust, rewarding you with a Heart Container.

In Four Swords Adventures
In Four Swords Adventures, this boss was designed to stop you from entering the Tower of Flames. This monstrous bird would swoop down up Link twice, then drop rocks upon him and his clones, then repeat the process. To defeat this boss, Link would have to daze the bird with bombs to help him destroy the mask. After the mask was destroyed, then he could finish the job easily.

Twilight Princess?
The Helmaroc King might be related to Argorok in TP, they both have similar names and looks, maybe the Helmaroc King is a more advance version of Argorok.