If the target wants to stop the hurt, they need to spend 5-10 mins (50-100 rounds of combat) taking their armor off or have dispel magic handy.
So on a target wearing metal armor, this spell could scale at 9th level to 9d8 recurring damage each round with no saving throw and causes disadvantage on attacks and ability checks. Phandelver and Below: The Shattered Obelisk Mordenkainen Presents: Monsters of the Multiverse
