But, there is a fair amount of source material (fighting games, several anime) where fighting just does not work like that - it's mostly one on one with only occasional many-on-one or one-on-many matches, never many-on-many fights. Team on team combat does not happen as the protagonists will break into solo fights, using lines like "Leave this to me", "or this is his fight, and his alone" to enforce 1-on-1 combat.
And systems that assume team on team combat often have mechanical breakdowns in one-on-one fights, where things are either too simplistic and/or much too lopsided.
But conversely, running one-on-one fights in an RPG system deep enough to be tactically interesting makes it so only one of the PCs is getting screen time during such a fight with the traditional small-group social RPG setup.
So purely in the interest of genre simulation (and to avoid acutally useful work on my own games), I would like to brainstorm hypothetical ways in which one could run an RPG with most conflict being one-on-one and yet keep multiple players engaged.
- Everybody takes turns, really long turns. In this setup fights are one on one, and they are resolved in sequence. Or at least mostly resolved, this is used frequently in movies, shows and comics for dramatic effect. This does not work well in RPGs as it outright requires players to be out of the spotlight for length periods
- Three-Ring Circus. In this setup, everybody takes short terms, just like the team-vs-team rules of the game, but nobody influences anyone else's one-on-one fight until they win their own first. This keeps everyone in the spotlight as much as normal, but can easily run into problems with suspension of disbelief and is subject to limited tactical depth and a greater chance of mismatch.
- Evil Twin - In this setup, fights are one-on-one, but you keep an additional player engaged by giving them the antagonist to run. This is an old trick for making MC's life easier, and can be combined into most of the other options.
- Tag Team. In this setup, only one PC fights at a time, but other PCs get to swap in as an interrupt when certain conditions are met. This is very metagamey and has issues with suspension of disbelief in RPGs, but is totally how a lot of video game fighters work. It has the drawback that only one player is active, but not quite as badly as really long turns since the inactive players are waiting for their cue to tag in.
- Moral Support. In this setup, only one PC "fights" at a time, but other PCs have abilities which provide bonuses to the fighter or unlock additional moves for the fighter to use. If you use support abilities which are expected to change round-by-round, this could be a decent way to keep all the players involved in a one-on-one character fight that didn't involve their character.
- Mid-Fight Flashback - a seemingly odd hybrid of Tag Team and Moral Support that seems to be the way a heckuvalot of anime works. You're all nerds, you've doubtless seen the anime where Dweeb the Impulsive fights Bishonan the Badass Badguy, until Dweeb takes enough of a beatdown that his teamate would be able to swap in if this were Marvel vs Capcom. But Dweeb is the combat character, so there is nobody else to tag in, thus instead a montage of other scenes is triggered - these can range from flashbacks to training montages to memories, to previously unseen speeches from greatful villagers about how Dweeb is their last hope, to memories of the Bishonan's villainy against Dweeb's love interest, to outright taunts from Upperclassman the Rival - but when the noncombat scene ends, Dweeb has attained new understanding and he's back in the fight with his combo meter charged.
What are other useful combinations?
What are benefits and drawbacks to handling things in various ways?