Cyclok

As Link reaches the top of the Temple of Wind, the door shuts behind him, and an Octorok riding a tornado descends to fight him. Cyclok is the cause of the whirlwinds that have prevented Link from entering the northwest quadrant from the eastern portion of the southwest quadrant.

On one of three spots on the ground, there will be a small tornado. By waiting for Cyclok to float above that tornado, and then sending a bomb up to it, the boss will be temporarily grounded, allowing Link to slash at it with his sword. As the fight goes on, Cyclok will sometimes go to the ground of its own accord, except still in its tornado. This will cause the smaller tornado to switch locations. Once Link defeats it, he gets more sand for his Phantom Hourglass, along with Nelly, the Fairy of Wisdom.