Enter the battle between innovation and power with the Pokémon TCG: XY Steam Siege Booster Box. As one of the most distinctive expansions of the XY era, Steam Siege introduced dual-type Pokémon, powerful Mega Evolution Pokémon, BREAK Evolution cards, and an exciting lineup of collectible chase cards that continue to attract collectors and players alike.

Steam Siege is best known for featuring fan-favorite Pokémon such as Volcanion EX, Mega Steelix EX, Steelix EX, Mega Gardevoir EX, Yveltal BREAK, and Xerneas BREAK. The expansion's unique dual-type Pokémon mechanic and strong lineup of Full Art, Secret Rare, and Mega Evolution cards helped establish Steam Siege as one of the most memorable releases from the XY generation.

This sealed booster box contains 36 Steam Siege booster packs, providing collectors with an excellent opportunity to chase some of the most sought-after cards from the XY era while building master sets and expanding their Pokémon TCG collections. Booster boxes remain the preferred choice for collectors seeking maximum pack openings and long-term sealed product investment potential.

Whether you're hunting for Mega Steelix EX, collecting BREAK Evolution cards, building a sealed Pokémon collection, or investing in a nostalgic XY-era expansion, the Steam Siege Booster Box offers exceptional collector appeal and long-term value.

As sealed XY products continue to become increasingly difficult to find, Steam Siege remains a desirable Pokémon TCG collectible thanks to its unique mechanics, powerful Pokémon lineup, and growing popularity among vintage-modern collectors.

Possible Chase Cards From Steam Siege

• Volcanion EX Secret Rare
• Mega Steelix EX Full Art
• Steelix EX Full Art
• Mega Gardevoir EX Full Art

Perfect For

• XY Pokémon collectors
• Mega Evolution Pokémon collectors
• Sealed Pokémon product investors

Product Details

Product Information

• Product: Pokémon TCG Booster Box
• Set: Steam Siege
• Series: XY
• Artwork: Pack Art May Vary
• Edition: Standard Edition
• Condition: Factory Sealed
• Language: English
• Includes: 36 Steam Siege Booster Packs

Additional Verified Details

• Official Pokémon TCG XY expansion product
• Features Pokémon EX, Mega Evolution Pokémon, BREAK Evolution cards, and Secret Rare cards
• Introduced dual-type Pokémon to the XY era
• Home to Volcanion EX, Mega Steelix EX, and Mega Gardevoir EX
• Factory-sealed booster box configuration
• Authentic Pokémon collector product