This game was sold as a special limited product to the people who had bought "Mobile Suit Gundam (機動戦士ガンダム)" on PlayStation 2 during the acceptance period from December 21, 2000 to January 31, 2001.
It's not a hibaihin since it could be purchased but I find it interesting to mention because it was not available on physical stores.
It has no barcode but a serial number instead.
Important notice :
In Japan, Gundam : the Battle Master series had 2 releases. The first was not released outside Asia. The second came out in the US two years later under the title Gundam: Battle Assault.
At the time, Mobile Suit Gundam Wing had started on Cartoon Network and was gaining popularity, so Bandai changed the storyline and mobile suit pilots to a Gundam Wing base, among other things. Particularly, the Hammer Hammer mobile suit was removed from the lineup and replaced with the Wing Gundam, though this new character is simply Zeta Gundam (which is still in the game) with a different visual design. Not only that, but this version removed the original intro and credits without replacing them.
In 2001, this US version was released in Japan, under the Gundam: Battle Assault title.
The game is the Japanese version of the US Gundam Battle Master 2 release.
(source : wikipedia)