The latest expansion set for the Pokemon Trading Card Game is called "XY-Ancient Origins" in the United States and includes 100 new cards, as of 2015. In Japan, the set is called "Bandit Ring." The set has two prebuilt theme decks available for purchase in addition to normal card packs.
"XY-Ancient Origins" is an expansion themed around the discovery and use of ancient training secrets and mythical artifacts for Pokemon battling. It heavily features the mechanic of Mega Evolution, which allows trainers to use Mega Stones to transform their Pokemon into more powerful creatures once per game.
A new and unique psychic-type basic Pokemon called Hoopa was also introduced, which cannot evolve but has a second form that is incredibly powerful. A number of new Pokemon-EX were added, which are usually basic Pokemon with improved health and attack stats. They also give more rewards to the opposing player when they are defeated. Some other new Pokemon introduced in the set are Sceptile-EX, Rayquaza-EX, Gyarados and Porygon-Z.
Ace Trainer is one of the new support cards, which forces players to reshuffle their hands into their deck and draw again. There are a number of new tool cards and energy cards that can buff a Pokemon's stats, as well as item cards like the Eco Arm and Paint Roller, which can help a player draw more cards or rescue cards from the discard pile. Also included are stadium cards, like Faded Town, which deals continuous damage to Mega Evolved Pokemon as long as they are in play.