This game isn't a bad game to play (If you have any friends you can still enjoy this game). The issue with the game is it's lack of players online for most if not often all the time. So if you are either A. Are tight on money or just like to conserve it, or B. You are a man who tries to get friends but can't find any, and finally C. If you are someone who is just so dedicated to being a lone wolf who doesn't want to make friends, then TRUST ME when i say this game is definetely not for you. Besides if you want to play a cooperative zombie game with friends you could just play Zombie Panic Source, or if there are not enough players on that game for you, you can also always get No More Room In Hell, which I should also mention both games are free as well. Now if you are someone who just desperately needs to spend money on everything or you are that guy who just thinks all free games are the worst thing to happpen to gaming, you could also just get Left 4 Dead or Killing Floor for your coop needs. What i'm saying is while Contagion isn't necessarily a bad game, there are many games out there that do something similar or just like it, that aren't as dead Contagion is
I always wanted a slow, Day-Of-The-Dead-esque zombie game, with punishing gameplay and accuracy-demanding gunplay, and when Contagion was announced I was hyped. Sad to say, this game has been abandoned by the devs. With severely underpowered melee and lackluster sneaking capabilities, shooting your way through everything is almost required. If you don't know exactly what you're doing on a map and plan ahead (using up all your inventory space in the process), you'll find half your time is spent backtracking and another third of it spent navigating. Solo is nearly unplayable (as this is a team-oriented game and all) and so is multiplayer by the sheer fact that once a teammate goes down, it only gets harder. Escape is the only mode worth playing, as all the other co-op modes are very unpolished and any PvP game boils down to you getting sniped.
CIn short, it has the potential to be fun if you play with friends and friends only (and turn off the god-awful PvP in a ♥♥♥♥ing co-op game). Otherwise, avoid this game.
Contagion is a small game which many do not know of, do not let that stop you. This game is very very addicting and I wish i played more. You can play online and multiplayer as well as single player. I would definitely recommend this game!