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The Chaos Kin (混沌の遣い Konton no Tsukai) was a monstrous beast that was sealed inside the Lunar Sanctum, but after Arlon was defeated the Sanctum collapsed and the Chaos Kin was released. It then took control of Palutena and imprisoned Pit's soul inside a ring allowing it to control his body. But Pit was soon able to return to his body and get back into the fight.
Pit soon confronted it in Skyworld and beat it. But it soon captured Palutena's soul and flew into its home, the Chaos Vortex, to eat the soul. But both Pit and Dark Pit flew in to destroy it. But even after it was destroyed and Palutena's soul was released, the ashes tried to possess Dark Pit. But regular Pit sacrificed his wings to save Dark Pit and allowed the ashes to drift forever in the vortex.