Cosmic Flare

“Target 1 "Stardust" Synchro Monster you control; this turn, if that Synchro Monster you control battles an opponent's monster, shuffle that opponent's monster into the Deck at the start of the Damage Step. If a "Stardust" Synchro Monster you control would Tribute itself to activate its effect, you can banish this card from your Graveyard instead.”