Level-5 has created a website that displays a rotating black cube. They have also tweeted an ambiguous messgae on their official Twitter page in relation to the box. The tweet asks, "What do you think is in the box?" At this time no additional information beyond this has been disclosed.
UPDATE: Block Box has been revealed to be a localization of Guild 01 to the eShop.
Black Box Teaser Website
Siliconera
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