Armored Cybern (PTDN-EN009) [Phantom Darkness]

Once per turn, you can equip this card to a "Cyber Dragon" you control, or to a Fusion Monster you control that lists "Cyber Dragon" as a Fusion Material Monster, OR unequip it to Special Summon this card in face-up Attack Position. Once per turn, while equipped to a monster by this effect, you can decrease the equipped monster's ATK by 1000 and destroy 1 face-up monster. (A monster can only be equipped with 1 Union Monster at a time. If the equipped monster would be destroyed, destroy this card instead.)