From the fires of Shiv to the darkness of Phyrexia, Urza seeks one thing: vengeance. The power of the planes comes to your game with new magic, new powers, and new ways to defeat the Phyrexian forces that stalk you. This 350-card set marks the beginning of the Urza block, which features new mechanics like Cycling, Echo, Sleeping Enchantments, and Growing Enchantments. —description from the publisher