Much to the chagrin of Half-Life fans, but to the pleasure of Left 4 Dead fiends, Valve announced a full sequel to its zombie shooter on Monday, set for a quick turn-around release on November 17.

The sequel will feature four new characters across five new campaigns set in New Orleans. Versus and Survival mode play will be supported for all of the maps out of the box, along with a new unannounced game mode. A fresh cadre of weapons, zombies, AI improvements and other additions are planned.

To get a handle on the situation, we took twenty to hit up Valve marketing VP Doug Lombardi and developer Chet Feliszek for some choice anecdotes on the new game. Included are finer details on the sequel's upgrades, shared frustration with stacking players, Left 4 Dead's connection to HBO's "The Wire," and more.

Shack: EA Partners helped publish the first Left 4 Dead, but yesterday's announcement didn't mention any publishing partner. Who's publishing?

Doug Lombardi: We haven't announced it yet.

Shack: But there is a publisher?

Doug Lombardi: There will be before we ship.

Shack: When did development on Left 4 Dead 2 start?

Chet Faliszek: Pretty much after Left 4 Dead launched.

One of the other things is.. we've all played [Left 4 Dead] now, we all play it now, we see things like [players] stacking in the corner and stuff, and we want to avoid it.

And also, we've got the marrying of the storytelling and the multiplayer. I think we did a good job with that on Left 4 Dead, but we think we're going to do a better job on Left 4 Dead 2. Part of that was we wanted to start with fresh new characters, fresh new setting, and follow their story as it goes across all of New Orleans. And all of this we are able to do because we have the AI director, which allows us to create these spaces and these events, and then it does kind of the hard work of creating that experience side of it.

Shack: Why did you decide to package the game as a full sequel, rather than DLC?

Chet Faliszek: So one of the things is, when we're looking at a map--

[Gabe Newell stops by to say hello, then quickly enters a private room.]

Chet Faliszek: In Team Fortress you can do one map, and it's a standalone map and it tells its internal story and you're good. In Left 4 Dead, when we started talking about new characters, all of a sudden we were talking about maps, then all of a sudden we were talking about campaign, and then director 2.0, hey, we're in the swamps.

And now we have to have new creatures in the game, we actually have dynamic pathing--we have all this stuff, and these aren't just incremental changes. These are big, technical changes. And to get that, and to hit our big mantra--making sure that the best way to play it is the funnest way to play it.

So, being Left 4 Dead 2, we have five campaigns, they're all going to have Versus and Survival mode out of the gate, as well as the regular co-op, and an all-new game mode. Not talking about that game mode yet, but it's going to be there. We also have the new Infected, like you can play the Charger right now in Versus. We have another one coming out a little later, and then another after that. We've got the melee weapons involved, we've got the chainsaw--we've got the frying pan.

Doug Lombardi: We didn't start off saying, "Hey, let's make a sequel for next year." We started off saying, "There's a bunch of really cool ideas. Let's put 'em all up on a whiteboard and figure out what's the best way to put these together and get them out there." And that's really fundamentally how Valve thinks about stuff. It's not like, "Oh, we need a product in this quarter," or whatever. We're not publicly traded; we don't have any of those weird pressures.

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Shack: Will updates for the original Left 4 Dead continue?

Chet Faliszek: Looking at Left 4 Dead 1, we have updates still coming out for it. Next week we'll be talking about the community map update, so that's coming. There's some other stuff we're not talking about yet, that's coming for that, that will explain why the Left 4 Dead SDK tools are different from previous ones. And then we still have four vs. four matchmaking coming. So we're not putting that to bed yet.

Shack: How will Left 4 Dead 2 interface with Left 4 Dead 1, if at all?

Doug Lombardi: We haven't really worked it all out yet. It's likely that it will be different on the different platforms. We really haven't made any final decisions, but it is something that we're looking at, and we understand that it's something that is on people's minds, and that there are more elegant ways to do it than others.

Some of the things that we're doing that we can talk about already is that, if you're using the SDK and making maps, it will work for either game. So we've got one or two elegant points that we can talk about now. [laughs]

Shack: What price-point should we expect?

Doug Lombardi: This is a full sequel.

Shack: So full price?

Doug Lombardi: Yeah. At the end of the day, this is going to be a bigger game than Left 4 Dead. It's five campaigns versus four, all five are playable in Versus mode, Survival mode out of the box, the new multiplayer game mode. Plus over 20 new weapons and items. It's a full sequel.

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