The 2007-08 Modified format of the Pokémon Trading Card Game (informally called HP-on and now referred to as Standard format) was a former Standard format used for Play! Pokémon organized play and in most sanctioned tournaments worldwide from September or November 2007 to August 2008.
The 2007-08 Modified format was announced on May 29, 2007, and was the first Standard format change to rotate out five sets (EX Deoxys, EX Emerald, EX Unseen Forces, EX Delta Species, and EX Legend Maker). At first, the play period slightly varied due to different release schedules in various regions for the first two Diamond & Pearl sets. As of Secret Wonders, released in November, the release dates for North America and Europe had realigned, causing the European Modified format to officially switch to HP-on. However, this had unofficially been the case since the release of Mysterious Treasures in late September.
- North America: September 1, 2007 to August 31, 2008
- Europe: November 1, 2007 to August 31, 2008
- 2007 Battle Roads Autumn
- 2007-2008 City Championships
- 2007-2008 State/Province/Territory Championships
- 2007-2008 Regional Championships (U.S. & Canada) only
- 2008 Battle Roads Spring
- 2008 National Championships
- 2008 World Championships