Sega gave their classic games star treatment with the Sega Ages 2500. These Japan-only compilations added extra features, art galleries, and sometimes even remakes. Gain Ground, originally an arcade game, was remade with 3D models. The Sega Ages version plays the same as the original which is a wacky game with samurai, knights, Vikings, robots, dudes with guns, and a Rambo wannabe.
The smorgasbord of characters makes Gain Ground unique and charming. The PS3 version has remixed music, an "extra game" mode to unlock when you clear Gain Ground, and the overseas arcade version.
Gain Ground was re-released as a downloadable PS2 Classic in Japan for just 800 yen ($8).