Ancient Gear Gadget (SR03-EN000) [Structure Deck: Machine Reactor]

If this card is Normal or Special Summoned: You can declare 1 card type (Monster, Spell, or Trap); this turn, if a monster you control attacks, your opponent's Spell Cards, Trap Cards, or monster effects (whichever was declared) cannot be activated until the end of the Damage Step. Once per turn: You can declare 1 "Gadget" monster's card name; until the End Phase, this card's name becomes that name.