2 monsters, including a Scrap monster
You can target 1 Scrap monster in your GY; Special Summon it, then destroy 1 card you control. If another face-up Scrap monster is destroyed by card effect, while you control this monster (except during the Damage Step): You can Special Summon 1 Scrap monster from your Deck, then destroy 1 card on the field. You can only use each effect of Scrap Wyvern once per turn.