Mournblade (5e Equipment)
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Weapon (greatsword), legendary
The Mournblade is a long, black steel blade with an onyx hilt with a deep red eye embedded in the center. You gain +3 bonus to attack and damage rolls made with this magic weapon. It has the following additional properties:
Soul Rend. Whenever you use it to reduce a creature to 0 hit points, the sword slays the creature and rends the soul, unless it is a Construct or Undead. Upon their soul being rendered, the targets body turns to dust and all objects not part of their body fall to the ground. A creature whose body and soul has been destroyed by the Mournblade can only be brought back through a wish spell. Upon rendering a soul. The user regains HP equal to the damage rolled for the fatal blow.
Soul Hunter. While you hold the weapon, you are aware of the presence of Tiny or larger creatures within 60ft of you that aren't Constructs or Undead. The wielder has advantage against being charmed or frightened.
Sentience. The Mournblade is a sentient Chaotic Evil weapon with and Intelligence of 16, a Wisdom of 12, and a Charisma of 18. It has hearing and darkvision out to a range of 120ft. The weapon can read, speak and understand Common and is able to communicate with its wielder telepathically. Its voice is deep and echoing. While you are attuned to it, the Mournblade also understands every language you know.
Personality. The Mournblade is cold, vicious, and seeks violence at any opportunity, It wishes to be used by a merciless creature who will embrace its destructive nature.
Soul Shredder. Upon rendering 1d12 + 5 souls, you will have access to a new innate ability forged inside the Mournblade. Once per day, after rendering a soul, the Mournblade may choose to enter into its true form. The blade shifts into a larger, jagged blade that seeps shadow. Until your next short or long rest, all attacks with this sword deal an additional 2d6 necrotic damage. Once the rest is taken, you must must make a DC 14 Constitution saving throw or lose 1d4 points from your Wisdom stat. Upon reaching 0 in your Wisdom stat, you become a slave to the Mournblade and are now under your DM's control. The only way to bring you back is through a wish spell.