Blade of Levistus (5e Equipment)
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Weapon (any sword), legendary (requires attunement)
This weapon has been touched by Levistus himself, ruler of Stygia. The blade of the weapon seems as if it's made of ice, though it's just as strong as steel, and the hilt, pommel, and guard are made of wrought iron, the handle wrapped in simple black cord. This weapon grants a +2 bonus to attack and damage rolls made with it.
Kiss of Levistus. Attacks made with this weapon deal an extra 2d8 cold damage. If the wielder rolls a critical hit on an attack, all creatures within 10ft must make a DC 16 Dexterity saving throw or take 2d8 cold damage and have their movement speed reduced by 10ft until the end of the wielder's next turn.
Servant of Levistus. The wielder may cast infernal calling as a 7th-level spell. Once this feature has been used, it cannot be used for one week after that.