As a kid growing up, I could count the number of friends I had on both hands, sometimes just one. I also lived a fair drive from most of them (about an hour round trip sometimes), so I didn't get out much. As such, I tend to gravitate to single player experiences, stuff I can play by myself. But I do have a particular love of co-operative stuff. I have always liked playing through things like Halo with a friend locally, and occasionally I will get swept up in some PC co-operative offering. The Left 4 Dead series is quite good, but doesn't have the hooks for long term play for me. Killing Floor was a brief obsession of mine, but I am not going to talk about that right now. Right now, I have only one game on my brain, and its Payday: The Heist.
In Left 4 Dead, there are rarely any tasks beyond getting from Point A to Point B. It occasionally breaks this up with bits defending from waves of enemies, or running around collecting needed items like gas. It's simple but effective. Payday adds in additional wrinkles, such as in the First World Bank level, where you need to monitor an automatic drill that jams periodically while also going to the other side of the level to erase security footage, while also keeping control of various civilians around the level. Also, the police are almost always trying to stop you in some way, either through brute force assaults or sending in special units through the vents while you think you have down time. Adding in just one more thing to worry about besides the enemies adds an extra level of tension. Thankfully, it never has more than three or four things to worry about, so it never becomes too overwhelming.
These overall objectives add an important element that many other multiplayer games on the market lack: a tension arc.
I have never really liked a multiplayer game that just involves killing things for this reason; each individual match lacks this important element. While the diagram above is the tension arc for a three act plot structure, in a good work of linear media (game, movie, book, etc.), a great many smaller pieces are also made up of tension arcs, even to the smallest things like shooting a gun (rising tension as you start to fire, increasing tension as you expend the clip on the target, and the denouement of reloading). This game uses these arcs extremely well. Police Assaults are a constant flood of law enforcement, and every time they come at you it gets harder and harder, but they almost always do end, after a while. Each objective takes time to complete, whether through direct interaction, such as herding a VIP you need to transport, or through only periodic interaction, such as with the aforementioned drill. Either way, there is an arc to the objective, from the low tension at the outset, or near the climax, when you have only 20 seconds left on the drill, but two teammates are down and bleeding, you are down to your pistol and two SWAT with riot shields are creeping towards you. It's really exciting what context can do to make a game more interesting.
I could go on about how authentic it feels to those modern heist movies, with the clown masks and brief audio vignettes before each level, or how they randomize just enough to make it interesting and unique each time (guard and civilian position, makeup and length of police assaults, even adding or subtracting objectives), or how you can complete some missions almost entirely by stealth and coordination, and only near the very end have to resort to violence. But to me, a lot of that is just icing on the cake. Now if you will excuse me, I have cash to grab.
Images from Photobucket, except where noted.