Threshold

Choose one of the following damage types: acid, cold, fire, force, lightning, necrotic, poison, psychic, radiant, or thunder.

For the duration of the spell, or until you end concentration with it, whenever the target creature takes damage of the chosen type, the damage must exceed 10; otherwise it instead deals no damage. If this damage does exceed 10, it deals the full amount rolled.

When you cast this spell at 4th level or higher, the value that incoming damage must exceed in order to be applied increases by 3 for every spell slot above 3rd at which the spell is cast, for a total threshold of 28 using a 9th level spell slot.