Mōryō

Moryo takes the shape of an enormous serpent whose elongated body runs a deep, dark purple, crowned by several dragon-like heads, four at the least. Crimson light burns in his eyes, his tongues show blue, and a paler violet glow radiates around the whole mass.

Cold indifference marks the demon. Even Yomi's sworn devotion earned no regard from him, and his single fixation is dragging the world into shadow so his Thousand-Year Kingdom can rise.

Long before the film's events, Moryo sought to wreck the world and rule a thousand-year realm, borrowing a shinobi clan's Ghost Army toward that end, until Miroku, high priestess of the Land of Demons, stopped and sealed him. His spirit was bound within the Land of Demons and his body within the Land of Swamps. United in body and soul, the demon could raise a nearly unbreakable army of stone and smother enemies in a blinding darkness, and his chosen host gained enormously amplified strength, though no ordinary human could contain his soul for long.

Generations later Yomi, descended from that clan, came to loose the demon as the stars aligned, offering his own body as a vessel since Moryo would fade without his true form. Inhabiting Yomi, the demon directed his four servants and his stone legion toward the shrine holding his body. He confronted Shion, Miroku's daughter, misled her, reclaimed his body, and burst free of Yomi, killing him. Naruto Uzumaki arrived to battle him, and after Moryo tried to absorb Shion, the combined chakra Rasengan of Naruto and Shion destroyed him.