Tessaiga (5e Equipment)
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Weapon (katana), legendary (requires attunement by a creature with a demonic ancestor)
This masterwork katana appears to be rusted and battle worn, its brother is Tenseiga.
You have a +2 bonus to your attack and damage rolls with this magic weapon. The wielder cannot die of old age and is immune to disease while attuned to this weapon.
Kaze no Kizu. As an action, the wielder may emit a 50 feet long and 5 feet wide cutting winds from the blade in a direction you choose. A creature in this attacks way must make a DC 17 Dexterity saving throw to take half of the 3d8 slashing damage and not be knocked prone if the creature is Large or smaller. The weapon regains use of this effect at dawn.
Bakuryūha. When you are hit with a melee attack, you can make a viscous attack back against the creature that hit you as a reaction. This attack deals 3d10 slashing damage. The weapon regains use of this effect at dawn.