Legend of Zelda: Twilight Princess HD - MiniBoss: Death Sword

Guarding the Spinner is the miniboss of the Arbiter's Grounds, Death Sword. Since he is a ghost, you'll need to damage him as Wolf Link before being able to fight him on foot. Once you have exposed him, shoot him with an arrow, and wait for him to stop circling you; dodge his sword attack, and counter. Rinse and repeat. After that, you'll get the Spinner, which is a fun new item that allows you to ride on rails.