Which finally brings us to the co-op. While campaign co-op in a Mass Effect title remains an unrealized dream, Bioware has added their take on the now-standard wave based survival mode for four players.
Your co-op career will begin by creating a character from one of the series' standard classes. To start off, you're restricted to human characters, though you will eventually unlock other races to choose from. Pick some colors, name your character (which is visible only to you, sadly), and you're off to matchmaking. Some basic filtering options are available finding a game (or setting up a private match): map selection, enemy force selection (Cerberus Operatives, Reapers or Geth) and challenge level. I've heard that some PC players may need to forward ports on their routers to get things working smoothly, which is unfortunate.
If you're just starting out, be warned that a few times I brought a fresh level 1 character into a match, I got booted by the host. Luckily, most people aren't jerks, and completing a round will gain you multiple levels and (mostly) remove the problem. Just be sure you aren't trying to bring a lowbie character to a Silver or Gold-level challenge. Additionally, though Bronze-level challenges can certainly be completed with moderate difficulty by two players, you'll want to ensure that there are at least three players in a match for better chances. If the difficulty is cranked, I would not advise trying it with less than a full group unless you are a bit of a masochist.
Matches take place on one of six maps, which you'll recognize as being shared with the N7 missions available during the campaign. Each match contains 10 rounds of galactic manshooting, capped off by a final escape sequence. For most rounds, you'll simply be fending off ever-increasing numbers of enemies that get more powerful as you progress, but every few rounds, an objective will be added to the mix. These objectives are instantly familiar to anyone who has played a competitive multiplayer game. Need to hack a computer? Capture and hold a control point for a set amount of time. VIPs spotted in the area? You'll have to kill 4 marked enemies under a time limit. Failure to complete these objectives in the time limit results in a game over, and no, you cannot restart a match from the current round. Luckily, you still earn XP and Credits for failed matches.
The final round is always a 2-minute retreat to an extraction point, and you'll be pinned down by the most powerful forces your enemy has to offer. If you make it out, congrats! You've not only earned valuable XP and Credits for your character, you've added about 3% readiness to your single player campaign's Galactic Readiness rating! This is where the controversy lies, but Bioware is insistent that you can still get the "best" ending without touching multiplayer. Considering I played a ton of it for this review, I can't comment on that assertion.