Earthbound Release (Maze of Millennia MZMI-EN022) - Rare Yu-Gi-Oh! Card

When a Level 6 or higher monster(s) is Normal or Special Summoned: Tribute 1 Level 10 "Earthbound" monster; destroy as many monsters your opponent controls as possible, and if you do, inflict damage to your opponent equal to the combined original ATK of those destroyed monster(s).