Yu-Gi-Oh! - Poseidra, the Atlantean Dragon (SDRE-EN001) - Structure Deck: Realm of the Sea Emperor - 1st Edition - Ultra Rare A single individual card from the Yu-Gi-Oh! trading and collectible card game (TCG/CCG). This is of Ultra Rare rarity. From the Structure Deck: Realm of the Sea Emperor set. You will receive the 1st Edition version of this card.