It was distributed as a bonus to 10 000 people who had reserved Over Blood 2. I don't know why but it's rather rare on sale... There is no video about it anywhere.
It contains a "Premium disc" entitled THE "EAST EDGE" FILE as well as a MISSION MAP 2 plus "α".
THE "EAST EDGE" FILE is a digital material collection that contains CGs and character profiles that do not exist in the main game. The MISSION MAP 2 plus" α " is an original map capture collection useful for the early stages of Over Blood 2.
Here is a brand new variant with postal printings on the top left corner. It is certainly the version you could get by sending back an application form (see here).
The disc inside might have a different serial...