Runelord's Response

Trigger A creature deals damage to you with a spell

You gain a measure of revenge immediately by twisting the magic used by the triggering creature. Spend a Mythic Point. The triggering creature takes 6d8 force damage, with a basic Will saving throw against either your class DC or spell DC using mythic proficiency, whichever is higher. At 14th level, and every 2 levels thereafter, this damage increases by 1d8.