Preview: Portal 2 (co-op)

Chris Grant: So, lucky us, after the first full day of E3, you and I were the only pair to play Portal 2 together, cooperatively, without Valve. Valve writer Erik Wolpaw has been giving the the demo while playing as the second player, but he said he thought we looked like we could handle it on our own.
Richard Mitchell: It was surprising to me how quickly we fell into step, actually. If you've played Portal before, it's kind of amazing how soon you start thinking cooperatively -- figuring out how you need two people to solve a given puzzle. It's a different experience, but it's still Portal.
CG: Valve's Erik Johnson told us that the cooperative experience is actually much harder and much more complicated than the single-player component. For example, you've got four portals to deal with instead of just two. Coupled with the obvious issues with verbal communication ("No, jump through that portal!") it definitely forces players to work together -- or not, if you're a bastard.
RM: We should definitely discuss the "or not" situations in a bit, but first I have to mention the tools that Valve added to make cooperative play easier. Wolpaw told us that one of the first things the team came up with was a way to mark walls for other players. Rather than just shouting out, "Hey, make a portal over there," you can actually target a specific location.
CG: Furthermore, you can use different icons for different actions. Look here, stand there, make a portal here -- that kind of thing.
RM: Kind of makes me wish you could do that in Left 4 Dead, instead of just screaming.
CG: Sure enough, it was all of 60 seconds before the necessity of needing to point things out was apparent. You press "Q" and it brings up a list of contextual icons that will stick where you're pointing. Press the "eye" and your partner will get a waypoint indicator asking him to look at your marker. The same goes for the "jump into this portal" icon. Those tools, coupled with some shouting, prove to be enough to help two (admittedly great looking) guys like us complete some pretty tricky puzzles.
RM: One of the great things about what we played was that even screwing up our meticulous plan was a blast. This is actually something else that Valve has really fleshed out: giving the players' characters (which are robots) some really great death animations. If, for example, you allow a descending ceiling to crush your partner -- completely by accident, of course -- you get to watch the poor robot do its damnedest to push the ceiling back up before it's inevitably crushed. Oh, and the new GLaDOS commentary? So great.
CG: Yeah, Valve had originally considered using Chell from the first game, along with another test lab partner (called "Mel") but realized that, because you'll probably be dying a lot, it made sense to use infinitely respawnable robots. And, like the rest of the characters in Portal, they each have unique looks and animations. And of course, GLaDOS is there in co-op as well, playfully pitting the two characters against each other. Wolpaw said the team originally scripted some of her dialogue to be addressed to two women – who she assumed had image issues – so now it sounds like GLaDOS is actually talking to robots with a weight complex.
RM: Which actually makes it even funnier. So, we haven't really talked about the mechanics of the puzzles yet: I think they're actually hard to describe -- much the way that the first Portal still is. Suffice it to say that the new mechanics are something you just "get" once you're able wrap your mind around the logic of the world. As Valve puts it: "Thinking with portals" -- only now you have to do it in co-op. There was actually a point where things just clicked. It kind of felt like being able to finish ...
CG: ... each other's sentences.
RM: Like in the first game, you kind of assemble a glossary of the feats you can pull off in Portal 2. During the demo, even some of the puzzles that needed split-second timing, became fairly second nature once we understood what two people could accomplish.
CG: One of my favorite new mechanics we saw was an energy bridge. It originates from a single point, and you can "extend" the bridge by placing portals in the world. In one puzzle, I shot an entry portal where the bridge ended, then you and I both had to jump using a springboard (or, as GLaDOS calls it, an "aerial faith plate"). While we were both in midair, I shot an exit portal on the far wall below us, which immediately allowed the energy bridge to extend beneath us and give us a place to land. Of course, it may have taken a few attempts to get the timing just right. And I already said I was sorry, Richard.
RM: The bridges were very neat. With four portals going at once, the same bridge can actually run in several different directions. It was starting to look like an M.C. Escher drawing at one point. Another new mechanic is the "portal fizzler," an energy field that causes all your portals -- but not your partner's -- to disappear once you pass through it. The same puzzle you just mentioned used one. The reason I couldn't extend the bridge myself is because the "aerial faith plate" launched me right through a fizzler.
CG: There's a cube – though not of the "companion" variety – that allows you to redirect an energy beam to activate switches (and kill each other!). Again, well-placed portals let you redirect energy beams all over the place. A particularly simple, though elegant puzzle required us to make a hole straight through two walls just by putting one portal on one end and another portal on the opposite end. Voila! Instant hole in the wall.
RM: Total Roger Rabbit moment there. Was Bob Hoskins consulted?
CG: I thought it was interesting that Valve's Erik Johnson told us that the co-op portion was "quite complicated" and "pretty challenging." While Valve is specifically tried to keep the single-player campaign accessible, all bets are off in the co-op mode. For example, the team avoided timed puzzles in Portal 1; however, Portal 2 co-op, Vavle has found that players enjoy making a plan and executing it. We had a stage that required triggering four timed buttons at once. As we each experimented with ways of reaching each button, we realized we'd never get to each one without some coordination.
RM: Right, this part of the demo reminded me a lot of the finales in Left 4 Dead. It's not so much thinking on the fly as it is coming up with a dedicated plan that you can execute on the spot. I also think Valve was right about this decision, as the timed challenge puzzles were the closest I ever got to real frustration when playing the original Portal. With a friend though, they become something else entirely.
CG: And that's the most surprising thing about co-op in Portal 2, I think. With a friend, it's something else entirely -- and it works better than I would've thought.
RM: I can't really think of a better way to put it. All I can say is that if you have reservations -- if you're worried that Portal 2 co-op might cheapen the experience you had with Portal 1 -- based on what we played, you should be able to put those fears to bed.
CG: Of course, to get those fears to the bed, you'll need to fire a portal over there ...
RM: Wait, where?
CG: Right ... over ... there.
RM: Oh, yeah, got it.

This article was originally published on Joystiq.