To be released on October 7th in Japan, this set is a set of 83 cards purely for Pokémon Emerald. In packs of 5 random cards. There are two different kinds of cards:

1. There are 64 Trainer Cards...possibly 2 on 2 to go with the new Double Battles
   
2. There are also 19 Map Cards, probably similar to the FR/LG cards, they will change the layout of the area

To use these, you need to have at least 2 badges to enter this place. Its a place just north of Mauville City. It is unknown what it is or what is is called, but as soon as there is news, It'll be here.