十～忍法魔界転生～•

Juu: Ninpou Makai Tensei

Story begins in 1638, during the Shimabara Rebellion, where a powerful swordsman who should have died is instead transformed by an arcane ritual into a demonic creature. As time passes, more swordsman facing death go through this transformation. What could these new, demonic swordsmen be planning? (Source: MangaHelpers)