Gear up for new ways to battle! Take control of Shiny Mega Gardevoir-EX to lay siege upon your enemies. Wield the dual powers of fire and water with the Mythical Steam Pokémon Volcanion. Use dual-type Pokémon to open the way to new, powerful strategies, and battle with the incredible Xerneas BREAK and Yveltal BREAK...all in the Pokémon TCG: XY—Steam Siege expansion!

The Pokémon TCG: XY—Steam Siege expansion includes:

Over 110 cards.
8 new dual-type Pokémon.
6 new Pokémon-EX, including two Mega Evolution Pokémon.
7 new Pokémon BREAK.

Each booster box contains 36 booster packs.