Earthbound Servant Geo Grasha

1 "Earthbound" Fusion Monster + 1 "Earthbound" Synchro Monster Must be Fusion Summoned. At the start of the Damage Step, if this card battles a monster: Change that monster's ATK/DEF to 0. If a monster(s) in your opponent's possession is destroyed by battle or card effect: You can destroy all cards your opponent controls. You can only use this effect of "Earthbound Servant Geo Grasha" once per turn. If this face-up card in its owner's control leaves the field because of an opponent's card: You can Special Summon 1 "Earthbound" monster from your Deck or Extra Deck.