Ōdachi of the Dawn Lion (5e Equipment)
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Weapon (ōdachi), legendary (requires attunement by creature who fights for a noble cause (talk to your DM as to what counts as a "noble cause"))
Ōdachi of the Dawn Lion is an exotic ōdachi made from pure crystals that deals an additional 2d8 lightning damage. While attuned to this sword you gain +2 Charisma.
Empowering Defeat. When killing a creature with this weapon you gain +1 Strength; this bonus can stack to a total equal to your proficiency bonus. The effects last for 1 in-game hour after the last creature you defeat; upon which the bonus is reset to +0. This effectively allows the user to maintain this bonus so long as he/she kills another creature within an hour of the last.
Lightning Strike. The wielder can use their action to expend a charge and fire a bolt of lightning from this sword at a creature within 60 feet dealing 3d8 + your Charisma modifier lightning damage on a ranged spell attack that uses your Charisma. The sword has a maximum of 5 charges and regains 1d4 + 1 charges at dawn.
Curse of Fate. Upon suffering damage, if you current HP drops to less-than or equal to 5 HP, you are filled with the strong desire to commit seppuku. You must make a Constitution saving throw at a DC of at-least 14; failure results in a death that cannot be undone by anything short of a wish spell. Upon succeeding the Constitution saving throw, the urge is dispelled until the next time either your health is depleted to 5 HP, or you draw this sword with less-than or equal to 5 HP.
Unyielding Morals. While using Ōdachi of the Dawn Lion, if the wielder attempts to strike any whom the wielder considers family or friends the wielded must make a Wisdom saving throw at a DC of 20. Upon failing the user will suffer half the damage he/she inflicts on the family/friend(s). However, if the wielder is successful, the wielder only has disadvantage on attack rolls and Charisma checks against your family or friends for 1 hour in-game.
The Ōdachi of the Dawn Lion can speak, read and understand Common, Elvish, and Undercommon. It speaks telepathically with its wielder.