Gain Ground started life as a largely unpopular 3 player arcade game. Surprisingly when taking into account the relative lack of commercial success it was ported to the Sega Megadrive/Genesis and Master System pretty swiftly. The gameplay is similar to Gauntlet but with a fantasy/sci-fi setting.
You and a friend have to fight your way through hoards of hostile enemies and kill each and every one or try to make it to the exit instead. There is a time limit so you cannot afford to hang about too long. You can choose between a range of playable characters each of which has different weapons and abilities. Along the way you can rescue new characters which have abilities more suited to the environment ahead.
There is more of a strategy element to Gain Ground unlike Gauntlet, however this additional layer of depth tends to confuse things. The playable character’s abilities vary greatly so some are much better equipped for tackling certain levels than others. The problem is there is no clear indication of what abilities each player possesses except for finding out through trial and error experimentation.
There's nothing really outstanding about the game - in fact, at times it's downright dull. It seems to have a cult following with Sega fans though, which might be the reason it's up for grabs on the Virtual Console so early in the day.
It is hard to recommend a below-average game such as this, but if you're after some Gauntlet-style action, then this is the probably the best place to look on the Virtual Console presently.