Black Vise

Created as a torture method for an ancient war waged between powerful spellcasters, the Black Vise is well known among mages, and inspires terrible fear in their hearts. When the Black Vise is placed on the head of a spellcaster, it automatically attunes to them. An unconscious or paralyzed spellcaster can not resist the Black Vise being placed on their head. A spellcaster attuned to the Black Vise loses the ability to cast spells while they remain attuned to the item. Any creature may cause the Black Vise use the spellcaster’s own magical potential against them, wracking their body with enormous pain as magical energy burns them from the inside out. When the command word is spoken by any creature not attuned to the Black Vise, the spellcaster attuned to the Black Vise begins to take damage every round equal to their highest level spell slot minus 4 (minimum 1). This effect continues until the command word is spoken again by someone other than the creature attuned to the Black Vise.