Greater Polymerization (Prismatic Secret Rare) [MP22-EN050-PrSR]

Fusion Summon 1 Fusion Monster from your Extra Deck, using 3 or more monsters from your hand or field as Fusion Material, and if you do, it gains these effects.
• This card cannot be destroyed by card effects.
• If this card attacks a Defense Position monster, inflict piercing battle damage.