Elemental HERO Electrum (LCGX-EN052) - Legendary Collection 2 Unlimited

"Elemental HERO Avian" + "Elemental HERO Burstinatrix" + "Elemental HERO Clayman" + "Elemental HERO Bubbleman"
Must be Fusion Summoned. While face-up on the field, this card is also WIND, WATER, FIRE, and EARTH Attribute. When this card is Fusion Summoned: Shuffle all banished cards into the Deck(s). Gains 300 ATK for each monster your opponent controls with the same Attribute as this card.