Scrap Fist

Target 1 "Junk Warrior" you control; if it battles an opponent's monster this turn while you control it, apply these effects.
● Your opponent cannot activate cards or effects until the end of the Damage Step.
● If it attacks a Defense Position monster, inflict piercing battle damage to your opponent.
● Double any battle damage your opponent takes.
● It cannot be destroyed by battle.
● Destroy the opponent's monster that battled it at the end of the Damage Step.