Japanese Pokemon Mega Dream Booster Box M2a

Booster Packs: Each booster pack contains 10 cards instead of the usual five, and includes a guaranteed Pokémon ex.

Chase Cards: The set will have a large amount of secret rares and reverse holos. There will be at least 50 secret rares.

New Secret Rares: Four new secret rares were revealed, including Special Art Rares (SARs) of Mega Gengar ex and Marnie's Grimmsnarl ex.

New Card Type: The set introduces "Mega Attack" rares, which are drawn in a "comic book" style with the Pokémon's attack name written over the artwork.