Living Lightning Rod

You have resistance to all attacks that deal lightning damage. Each time you get hit by a lightning attack you gain a charge that adds +1 to any damage rolls that deal lightning damage that can be stacked up to 3 times. After gaining 3 charges if you get hit by another lightning attack you will explode with electricity dealing 5d8 lightning damage to all creatures within a 25-foot radius, afterwords your charges will reset.