Your search for "Fusion Substitute LDK2-ENK31" revealed the following:
Fusion Substitute - LDK2-ENK31 - Common - 1st Edition from Legendary Decks II 1st Edition, available at 401 Games Canada. Rarity: Common Card Text:(This card's name is always treated as "Polymerization".)Fusion Summon 1 Fusion Monster from your Extra Deck, using...
Fusion Substitute - LDK2-ENK31 - Common - Unlimited (2020 Reprint) from Legendary Decks II 2020 Reprint, available at 401 Games Canada. Rarity: Common Card Text:(This card's name is always treated as "Polymerization".)Fusion Summon 1 Fusion Monster from your Extra Deck,...
Fusion Substitute - LDK2-ENK31 - Common - Unlimited from Legendary Decks II Unlimited 1996 Print, available at 401 Games Canada. Rarity: Common Card Text:(This card's name is always treated as "Polymerization".)Fusion Summon 1 Fusion Monster from your Extra Deck, using...