King of the Swamp (LCYW-EN256) - Legendary Collection 3: Yugi's World Unlimited

You can substitute this card for any 1 Fusion Material Monster. When you do this, the other Fusion Material Monster(s) must be the correct one(s). Discard this card from your hand to the Graveyard to add a "Polymerization" from your Deck to your hand. The Deck is then shuffled.