Biped gets its name from a duo of diminutive robots, sent to Earth in order to reactivate a series of beacons. You and another local player will guide these little guys through a series of stages, working together to overcome various obstacles as a pair. Co-op concepts don't get much more straightforward than this, but the game presents some unique challenges that are trickier than they first appear.
You can play alone, but it's clear this is meant to be a co-op experience. Fortunately, the barrier to entry is very low; actions are all controlled using the thumb sticks, each representing the respective leg of your robot. To walk, for instance, push the sticks forward and release one after the other. You can also glide around by pushing both sticks together, which gets you around much faster. Having controls almost exclusively mapped to two inputs means the game is very accessible, and you'd be surprised how creative the levels get. Sometimes you'll be forced to take one step each in sequence, others you'll be tethered together -- there's no shortage of ideas here.
Except, there kind of is. Biped is very short -- you and a friend could easily finish this off inside two or three hours. It means that every stage brings fresh ideas to the fore, but it's over before you know it. There are ways to extend your playtime; you could track down all the coins, which you can cash in for cosmetic items, or try your hand at the harder modes that unlock as you finish each stage. It's all good fun while it lasts, with some genuinely clever design, but you can wrap it up pretty fast. If you want something quick and fuss free to play with a pal, though, Biped is a charming little game worth trying.