When your opponent activates a Spell Trap Card while you control a Magikey Ritual Monster or a Magikey monster Special Summoned from the Extra Deck: Negate the activation, and if you do, destroy that card, then you can declare 1 Attribute, and if you do that, for the rest of this turn all face-up monsters your opponent controls become that Attribute. You can only activate 1 Magikey Unlocking per turn.