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Devil's Runeblade
Weapon (any sword), rare (requires attunement)
You have a +1 bonus to attack and damage rolls made with this magic weapon.
Rune of Accuracy. When you attune to this weapon, choose either Intelligence, Wisdom, or Charisma. When you make an attack with the weapon, you use the chosen ability modifier instead of Strength or Dexterity for its attack and damage rolls.
Rune of Fury. As a bonus action, you can activate this rune and cause the weapon to begin pulsing with infernal rage. While pulsing in this way, damage dealt by the weapon ignores resistance to fire damage, and whenever you hit a target with an attack using this weapon, the target takes an extra 1d8 fire damage. This effect lasts for 1 minute. It ends early if your turn ends and you haven’t attacked a hostile creature since your last turn or taken damage since then. Once activated, this rune can’t be used again until the next dawn.
Curse. When you score a critical hit with this weapon, you take psychic damage equal to the ability modifier you used for the attack. In addition, if you miss with an attack using this weapon while the Rune of Fury is active, you take 1d8 fire damage.