In the interest of maintaining a healthy tournament environment, Pokémon Organized Play removes older sets from the Modified format at the beginning of each new tournament season. Each rotation challenges existing players to create new strategies while enabling new players to get into Organized Play with a minimal investment.
The 2013 season will be starting on July 9th so that players can get an early start on working towards the 2013 Pokémon World Championships, but in order to avoid confusion we will rotate sets on the more familiar date of September 1st.
The 2012 Pokémon World Championships being held on August 10th–12th in Waikoloa, Hawaii, will use the 2012 format and rules as are currently listed.
The Modified format for the 2013 season will consist of the following expansions:
Black & White
Black & White—Emerging Powers
Black & White—Noble Victories
Black & White—Next Destinies
Black & White—Dark Explorers
BW Trainer Kit
Black Star Promo Cards BW01 and higher.
In addition, future Pokémon TCG sets will become legal as they are released, per the Pokémon Organized Play Tournament Rules.