Ashak-Tal, the Crown of Undeath (5e Equipment)
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This ancient crown was once worn by the first wizard to discover the secrets of necromancy. It was forged from black iron by duergar slaves, set with rubies shaped by Deep Gnomes and cooled in Drow blood. The frontal spine is created from the bones of a slain Dracolich. Wearing the crown has the following benefits:
Magic Item. When you cast Animate Dead, you can target an extra 1d4 corpses or skeletons per casting. When you cast Create Undead, you can create one additional ghoul. The crown has 30 charges, and regains 1d10 + your Charisma modifier expended uses daily at dawn. You can use an action to spend one or more of these charges, and depending on the charges spent you gain one of the following effects
Any undead summoned this way require a corpse or pile of bones within 120 feet of you of the creature type you are attempting to summon.
At the start of each of your turns, any undead within 120 ft of you that is not already under your control must pass a Charisma saving throw equal to your Spell Save DC or fall under your control, following your orders to the best of its ability.
Unholy Entropy. You can use an action to destroy an object within 30 ft of you that can deal radiant damage that does not have a Charisma score and isn't being worn or carried by a creature. If the chosen object has a Charisma score, it must make a DC Charisma saving throw or be destroyed. Artifacts have advantage on this saving throw. If the chosen object does not have a Charisma score and is being worn or carried by a creature, that creature makes a DC Charisma saving throw instead; on a failed save, the chosen object is destroyed. Once this ability has been used, it can't be used again until the next dawn.
Curse. The first time attuning to the artifact you must attempt a DC 15 Charisma saving throw or be Charmed by the ancient evil inside the crown. While you are Charmed by the artifact, you can't voluntarily end your Attunement to it, and the artifact casts geas on you at will (Wisdom save DC 18), urging you to work toward the evil ends it desires. The DM will decide what task the artifact wants you to complete. The only means of removing the curse is by the Remove Curse spell or by wish.
Sentience. The crown is a sentient artifact with Int 20, Wis 14 and Cha 18. It has hearing and darkvision out to 120 feet.
Personality. Ashak-Tal desires its wearer to rule the living and undead across the world, and be the greatest necromancer ever. It presses its wearer to seek out new dark secrets and magical treasures. It hates gods of undeath with a passion, and strives to destroy such beings as Orcus. It attempts to drive its wearer to acts of evil in order to gain power.