Armory Arm (Quarter Century Secret Rare) (RA03-EN213) - Quarter Century Bonanza 1st Edition Quarter Century Secret Rare

1 Tuner + 1+ non-Tuner monsters
Once per turn, you can either: Target 1 monster on the field; equip this card to that target, OR: Unequip this card and Special Summon it in Attack Position. While equipped by this effect, that target gains 1000 ATK. If that target destroys a monster by battle and sends it to the GY: Inflict damage to your opponent equal to the destroyed monster's original ATK.