Alien Soldier is a high-octane "boss rush" style run-and-gun that was released late in the Mega Drive's life. While the US release was available on the Sega Channel, American hardcore gamers had to wait until 2007 to see a proper release on the Wii Virtual Console. That said, there were plans to include upward of 100 bosses in the game, but time constraints forced the developers to include only 26.
Pictured is one of the many bosses planned for the game, but which was ultimately scrapped. While it was assigned an ID, the code for this boss doesn't work.