Squad goals: Gain Ground made team-building a blast

At first glance, Gain Ground appears to be retreading old ground. With its chunky combatants and sorta top-down view, it looks rather like teeming mega-brawler Gauntlet broken up into bite-size chunks. Instead of a sprawling, eight-way-scrolling dungeon with enemies crammed fractiously into corridors like commuters on a rush-hour train, you are presented with a single screen - often a rather sparse, scraggly green-brown field more suited to a mid-tier music festival than the glorious crucible of combat. Gain Ground has no gold to collect, no food to shoot. There are still plenty of baddies, though, and it's your task to wipe them out as a warrior of your choosing.

Perhaps you fancy a turn as the bald spear-chucker with a handlebar moustache who can shish kebab enemies camped on higher ground? Or maybe you prefer to play as a trigger-happy lady commando packing stick grenades. It feels like a vertical slice of Gauntlet - combat with the training wheels on, a primer in how to fight effectively when outnumbered. It eases the player into things, and gives you enough agency to feel like you're in charge. There's also a sneaky byproduct: when you mess up, it's tangibly your own fault.

What I loved about Gain Ground back in the day, and still love about it now, is the way it literalises the old three-lives gaming trope. You start with a trio of characters, and once they're all dead, it's game over. But you can swell your ranks by picking up new recruits along the way - frozen, slightly shrunken fighters who look like garden gnomes placed incongruously on each battlefield. Collect one and successfully steer them past the barbarians and angry knights to the exit zone, and they return to actual size and are added to your roster for future levels. Play with a little tactical care and before long, you can assemble an Expendables-style squad with a broad spectrum of overlapping specialities. You've gone from just three lives to seven, nine, a dozen.

That's when each screen starts to become more of a conceptual puzzle than random fragfest. Assessing the placement and firepower of enemies before you deploy your warrior transforms you into a pistol-packing player-manager. The initial question: who is the right recruit for this level? You analyse, strategise, then mobilise: lady commando FTW. But since no battle plan ever survives contact with the enemy, then you have to wing it. Your overpowered but lumbering rocket launcher dude buys the farm, and even the fleet-footed bowman is sadly overwhelmed. Now it's down to the bald spear-chucker to save the day. Levels could be completed either by defeating all enemies or expediting each of your squad, in turn, to the exit zone - running the gauntlet, if you like. The latter option seemed far more appealing when you were down to two troopers.

Gain Ground started life as multiplayer arcade cabinet, but I only ever played the Mega Drive version. Originally released in 1991, it apparently expanded the game to 50 levels from the original 40. Crucially, though, it wasn't my Mega Drive I experienced it on - it was a friend's machine with only one joypad. Anyone who has played turnabout with a controller knows that slightly shameful feeling of wishing your pal would hurry up and die so you can have your go.

At some instinctual level, that's what I found so appealing about Gain Ground: having the accumulation of lives placed so directly into the player's hands. Play tactfully and you could artificially extend your turn. There were some external constraints - a timer ticking down on each level added a sense of urgency - but this constant team-building exercise created an experience that was fluid in a way that Sonic, Altered Beast or Revenge of Shinobi couldn't match. Perhaps my memories would be less vivid if there had been the opportunity to play the simultaneous two-player mode, which would presumably add a whole other layer of gameplay, coming up with two-man fireteam tactics on the fly. But if my friend had possessed two joypads, we would likely have spent all those hours of Gain Ground grind playing Madden or Streets of Rage 2.

Not actually owning the game might explain why it never occurred to me to read the back of the box, which explains what the hell is going on. It was only when I picked up Gain Ground on the Wii's virtual console many years later that I did some research into the framing narrative, which helps explain why dwarves with longbows are fighting alongside cyber-guerillas. The Gain Ground of the fiction is a malfunctioning WarGames-style military simulator loaded up with scenarios and combatants from throughout the ages: Battlefield meets Bill & Ted.

It's a premise that elegantly justifies the mish-mash of historical warriors and helps explain away some of the necessary gaming scaffolding. There's no reason why the exit of each level in Gauntlet should be signposted as such. In Gain Ground, the clearly marked exit zone - a yellow box that literally looks like a HUD overlay, particularly incongruous among the blasted turf and scuffed stonework of the early levels - can be explained away as a feature of the simulation.

Having a sporadic experience of Gain Ground also kept an entire facet of the game obscured. Playing with a friend impatiently waiting for their shot, it never occurred to me to increase the difficulty level. But switching it up from normal to hard unlocks all 20 playable characters from the start. This completely upends the game. At first, it was just a thrill taking characters I'd never clapped eyes on for a tentative test-drive, getting to grips with various elemental mages, a chap who looked like M Bison with a flamethrower and a surprising number of boomerang-throwing valkyries. It's an exhilarating ride, until you twig that there are no new recruits to replace your squad in hard mode, so as you progress and lose fighters along the way, your talent pool will never be topped up. In truth, much as I love the samurai who can summon whirlwinds on a whim, I think I prefer the standard mode, building up my squad one fighter at a time, like the world's most belligerent HR department.

Right now, the Mega Drive is staging a rather unlikely comeback: with Christmas approaching, the various redesigned plug-in-and-play incarnations of the classic console are apparently some of the most in-demand items on Santa's list. Gain Ground tends to be one of the baseline titles thrown in as part of any pre-loaded games catalogue, alongside Sonic, Columns and other such Sega perennials. It may never be as beloved or iconic as Gauntlet, but it genuinely pleases me to think that two warring siblings might bond over Gain Ground this festive season, grudgingly passing a joypad back and forth, burrowing into this sometimes thorny game and generally restoring peace on Earth, and good kills to all men.