The Ultimate Reigai (最強の霊骸 Saikyō no Reigai; literally "Strongest Spirit Body") is a variation of Reigai (霊骸 Spirit Body) created by Muramasa Sumato. As the name implies, the Ultimate Reigai is prided as the strongest Reigai in existence, and is the culmination of years of research. Muramasa considers it one of his greatest accomplishments.