This is a Japanese Booster Box.
 
Magic The Gathering Jumpstart box let players new and returning alike mix, match, and enjoy the mayhem of unique themes with each latest release. Jumpstart packs in The Brothers' War follow the original Jumpstart release where each pack is a hidden theme to discover when you open, and shuffling any two packs together is all you need to be ready to play.
 
Each Jumpstart booster includes a half deck (20 cards). All 20 cards fit a theme, and most themes have multiple variations. The packs feature cards from the main set, including a rare or mythic rare, two foil basic lands, and a mechanically unique rare especially designed for the Jumpstart pack