Undone Seal

Undone Seal is the Japanese fourth and final main set of the ADV era, with a theme of ancient ruins and the legendary Regis. The set has 83 cards and focuses on Pokémon-ex, with the most recognisable cards being Regirock ex, Regice ex, Registeel ex, Groudon ex, Kyogre ex, Metagross ex and Ninetales ex. The series' atmosphere is rounded off by the stadiums Island Cave, Ancient Tomb, Desert Ruins, High Pressure System, Low Pressure System and Magnetic Storm and the trio of Ancient Technical Machine [Ice], [Rock] and [Steel] cards.