Elemental Hero Dark Neos [POTD-EN033] Ultimate Rare Code of the Duelist Set: Commander 2017 Type: Legendary

Set: Commander 2017 Type: Legendary Artifact — Equipment Rarity: Rare Cost: {4} Whenever Hammer of Nazahn or another Equipment enters the battlefield under your control

Set: Legends Type: Instant Rarity: Uncommon Cost: {U}{U} Cast this spell only during an opponent's turn after their upkeep step

Special Summon 1 Normal Monster from your Deck that includes "Elemental Hero" in its card name

but how could that be

Elemental Hero Dark Neos [POTD-EN033] Ultimate Rare Code of the Duelist Set: Commander 2017 Type: LegendarySet: Power of the Duelist Card type: Fusion Effect Monster Rarity: Ultimate Rare Attack: 2500 Defense: 2000 "Elemental Hero Neos" + "Neo Spacian Dark Panther" This card can only be Special Summoned from your Fusion Deck by returning the above cards from your side of the field to the Deck. (You do not use "Polymerization".) You can select 1 face up Effect Monster on the field if it''s not already selected by this card. While this card is face up on