Purgatory Knights, Jackknife Dragon

■ [Call Cost] [Pay 1 gauge & Put this card on top of a 《Armordragon》 monster on your field]

■ Counter [Act] Destroy a 《Armordragon》 monster on your field. If you do, destroy a monster on your opponent's field. You may only use this ability once per turn.

■ Soulguard