Boon of the Hallowed Necromancer (5e Epic Boon)
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Boon of the Hallowed Necromancer
Prerequisite: Able to cast 1 spell
As an action, choose an undead creature within 60 feet that is either under the control of another creature or has an Intelligence of 6 or lower. If the undead has an Intelligence of 6 or lower, and its soul is present or free and willing to return, or the undead has been freed from another creatures control, it regains the scores, skills, and features it held in life but retains the physical statistics of the undead creature it is. If not, the undead creature is destroyed. You can use this feature up to your spellcasting modifier + profeciency (maximum of 7) times per long rest.
You can use your intelligence instead of charisma for persuasion checks against undead.