This multiplayer-only Bomberman release is exceedingly rare and seems to have been produced for demo kiosks, tournaments, or both.
Users Battle is a Bomberman game for the PC Engine, released only in Japan. It bears a 1990 copyright, just like the original release of Bomberman for the platform. Additionally, it plays the same title screen music upon boot, but it has a different title screen, only allowing for multiplayer play for two to five players. It lacks the skull mode option of the full Bomberman release, but otherwise shows similar menus and styles to Bomberman's multiplayer mode.
It is believed that Users Battle was created in extremely limited quantities for use at tournaments, demo kiosks, or both. Some online sources estimate the number of cards produced at around 1,000.