The Master Deck Build Box EX (マスターデッキビルドBOX EX) was released in Japan on September 14th, 2012 for 4200yen. The box contains 140 cards chosen by top players. There are 51 different cards and the remaining cards are doubles. The box also includes a card case and a Master Deck Build Book. Below is the commercial for the deck build box.

Master Deck Build Box EX Commercial

Source: http://mdb.pokemon.co.jp/mdb/

I wonder if they'll ever release that box outside Japan... might be a good way to get some great cards, though it's not aimed at collectioners (so many doubles).