Argorok is a Twilit Dragon that resides in the skies over Hyrule. In The Legend of Zelda: Twilight Princess, it attacks the City in the Sky. It is the boss of the dungeon. To defeat it, Link uses the Double clawshot to attach himself to its tail, and use the Iron Boots to weigh it down and drag it to the ground.
After doing that a number of times, the dragon's armor falls off, and the second phase of the battle happens. Several Peahats come out of the ground and fly around the top of the arena, allowing Link to clawshot onto them. Argorok tries to breathe fire on Link, and while he does so, Link clawshots from peahat to peahat until he gets behinnd Argorok. The clawshot is used to attach to Argorok's back. When on the back, Link stabs him.