"The resentment of all souls lost at sea manifested itself as
this boat-sized starfish. Avoid the foam it spews from its mouth and its long
arms to protect yourself from being dragged to the sea floor."
The Asteroidean mainly fights with large orbs that it throws at Chibiterasu, which must be dodged. It will also attempt to throw itself into Chibiterasu for heavy damage (it is invulnerable during this time). The first thing he must do is cut off all five of the Asteroidean's arms; this is accomplished with a combination of attacks with his Divine Instrument or offensive Celestial Brush Techniques. When an arm begins to glow red, it is a sign that it is about to be severed.
After all five arms are gone, the Asteroidean will be very vulnerable to attack. However, it will also become more aggressive, and will bounce around the arena much more wildly than before. In addition, it will use its most deadly attack: a concentrated beam of water. It will either fire it in a straight line in Chibiterasu's direction or follow him around. Chibiterasu most avoid this or else suffer a lot of damage. If the Asteroidean fires the beam in a straight line, it is best to get behind it and attack while it is firing; otherwise, avoid the beam until it ceases fire.
After it is defeated, Chibiterasu and Nanami may continue into the Sage Shrine.
- Asteroidean's name comes from Asteroidea, the class of animals that starfish belongs to.