Sky Striker Mecha - Eagle Booster (MP19-EN265) [2019 Gold Sarcophagus Tin Mega Pack]

If you control no monsters in your Main Monster Zone: Target 1 face-up monster on the field; that target is unaffected by card effects this turn, except its own, and if you have 3 or more Spells in your GY, it cannot be destroyed by battle this turn.