Death Sword

Death Sword is the mini-boss of the Arbiter's Grounds dungeon in Twilight Princess. The Death Sword is one of the few creatures, Poes included, that reveal their true form when seen through Wolf Link's finely tuned wolf senses; the body of the Death Sword is normally invisible to the naked eye.

Strategy
When Link enters the room, the Death Sword is found embedded in the ground, bound by ropes. Cutting one of the ropes binding the Death Sword causes the evil magic within the blade to awaken and burn away the rest, thus beginning the battle. Link must transform into wolf form and use his senses to see the Death Sword's master. When it attacks and gets its sword stuck in the floor, Wolf Link must jump at it and start biting to make it visible. Afterwards, he can shoot it with arrows while it is floating in the air to stun him. Alternatively, he can use the Clawshot or the Gale Boomerang to do the job. It then flies in circles around Link, and finally attempts to strike him with its sword, at which point it gets stuck again, leaving its head vulnerable. Repeating this process a few times puts an end to the Death Sword, and Link is free to claim the Spinner in the next room.

Design
Death Sword shares its French name, Faucheur, with Gomess. The name is an allusion to the, who is known in French-speaking regions as la Faucheuse.

Before the battle with Death Sword begins, its eponymous sword is embedded in the floor, with a myriad of ropes adorned with tying it down. Ofuda are a type of real-world talisman that are generally used with the intention of warding off accidents, but a concentration of this magnitude would indicate an attempt to seal off an extremely evil entity.

The demon's lower spine is bent to the side, but this is obscured by its cloak.

Theory
The on the ropes origianlly tying the sword down indicate that they are meant to be keeping some sort of evil at bay. The sword's origin clearly lies with Ganon, as it disintegrates into twilight after being defeated, but the demon itself transforms into a swarm of flies and flies away. It is possible, then, that the demon was already in existence before Ganon arrived, but given physical form by Ganon's sword, and then sealed away by the inhabitants of the Gerudo Desert to protect themselves.

Trivia

 * Both Death Sword and Phantom Zant share a unique mini-boss theme.