This Feat can only be taken by character cannot cast spells, would it be from a class feature like "spellcasting" or "pact magic", or a feat like the "magic initiate" feat.
When you choose this feat, choose one 7th or higher spell from any class spell list. This feature has a number of charges equal to your proficiency bonus, you regain all of your charges at the end of a long rest. When all of the requirements (V, S, M, action cost, etc...) of the spell are met, roll a d100, if the result of the dice roll is equal or lower than 5 + your character level, the spell is cast, if not, you lose one charge.
You can change the spell at the end of a long rest. You cannot access spellcasting abilities without losing this feat.
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