Helmaroc King

In The Wind Waker
The Helmaroc King is a monstrous bird that was manipulated by the evil Ganon. The bird was designed to do dirty 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. The bird has a habit of getting it's beak stuck in the ground, making it open to attack. It also has trouble stopping itself from slamming into the towers around it's battle arena, the pinnacle of the Forsaken Fortress.

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 the the mask. After the mask was destroyed, then he could finish the job easily.