Aside from co-op, Kane & Lynch also features a cool multiplayer mode for up to eight players called Fragile Alliance. As described by the developers, Fragile Alliance is neither cooperative nor competitive, but "manipulative." In reality it's all three, and we've never played a multiplayer shooter that inspired as much distrust and paranoia in us and everyone around us.
Fragile Alliance sessions are divided into three to five rounds, which last for three to seven minutes each. When each round begins, all the players are on the same team (sort of), as mercenaries hired for a big heist. The idea is to run around the level - which in this case was the big, opulent bank from the story mode - and gather up the money that's stored in strategic spots - in the registers, on the persons of murderable bank employees, in secure cases at the loading dock, etc. Teamwork is almost essential to making it out alive, as you'll need to fight your way through heavily armed cops to get to the cash and your eventual getaway. The kicker is that teamwork is also one of the easiest ways to get killed.
See, winning at Fragile Alliance is all about making it to the getaway van with the most money, which can then be used to buy better guns and armor between rounds, which in turn makes you less reliant on teamwork. The thing is, if you see an opportunity - like, say, a teammate carrying loads of cash, near the exit, who's just finishing off the last few cops in the area - you can gun him down, take his cash and make a beeline for safety.
There's a catch, though - once you turn traitor, your teammates will all be able to see that you've done so, and if they kill you, they'll net a fat cash bonus in addition to whatever money you were carrying. Additionally, players who get killed will come back to life as armored cops, and if they were killed by another player, they'll get a bonus for gunning down their killer. So if you decide to take the bastard route to riches, be prepared to fight off everyone else at once (again, this is easier if you've been able to buy some cool equipment).
So, getting lots of money will help you win, but it'll also paint a big fat target on your back - and that goes double if you've just shot someone in said target. The risks are high, but so are the rewards - trust no one, watch your back and get ready to hate teamkillers like never before.