Dustin Browder's game development career stretches back more than 15 years, to when he worked at Activision on games like MechWarrior 2: Mercenaries, then moved to Westwood Pacific (eventually merged into Electronic Arts Los Angeles) to work for six years on numerous real-time strategy games, mainly in the Command & Conquer series.

In 2005, he joined Blizzard as the lead designer of the feverishly-anticipated StarCraft II -- and now he's back at Activision, in a sense, with last year's Vivendi/Activision merger.

Gamasutra recently sat down with Browder to discuss the inevitable difficulties that come with updating a 10-year-old game while trying to steadfastly avoid feature creep -- and why even after more than half a decade making RTS games, he still wasn't fully prepared for a lead design role at Blizzard.

With StarCraft II, you've said you're trying to avoid making a game that is significantly more complex than StarCraft, even as many individual elements change. How do you make the call as to what stays and what goes?

DB: It's just really tough. We have to make these calls on a daily basis. There were for a long time, and there's still a little bit of it, big debates on the team as to what is enough and what is not enough. What is too much?

We just walked the line, and we look at stuff that we sort of feel is core to the experience: "This is a defining element of the Zerg. We have to have the creep. It's defining." Or, "Siege tanks are a defining element for the Terrans." Then we look at elements where we'll say, "This was fun. We love these things. The fans have obviously been using them. Vultures and spider mines are huge -- but they're not defining elements. You could live without them. I can imagine the Terran army without these things."

So it's a combination of conceptual elements and mechanics. Where we think we can do better, we'll try do better. Stuff that we feel conceptually is not necessary, we'll remove. We've always felt that solo play and Battle.net were the areas where we could really do some stuff that was crazy, that was new and really interesting. And multiplayer really needed to harken to the game's legacy, while at the same time creating enough strategies so you don't think, "Well, I've played this game for ten years, guys. What are you giving me here?"

We want to have enough that it's still fresh. I think we're walking the line pretty well right now.

Even between the single-player and the multiplayer, there have been design differences that mean there are discrepancies in terms of what units are available.

DB: Totally.

Do you worry about that being unintuitive, especially for people who are new to StarCraft?

DB: Not really. We did for a little bit, but then we looked back at our previous games and realized that our solo campaigns have never prepared anybody for an online experience at all. That never worked, right? We always sort of touted it that way -- "It's going to prepare you" -- but it never really did.

Looking back at that, we feel that never really works anyway. This lets us make a much more compelling solo play experience. It can run free and be its own gameplay experience with all kinds of units and all kinds of upgrades, which wouldn't have been possible if we'd restricted ourselves to only the multiplayer set, because the multiplayer wants to become small.

It wants to be reasonable. It wants to be enough that you can keep everything in your head -- so not only do I know what I can do next, but I know what you can do next, and I can play the game in my head a little bit before we actually engage.

You want that sense of there being a very limited number of opening moves in chess, and then a larger set of second moves, and so on.

DB: Yeah. And how many moves can I think ahead of you? That's determining whether I can win or not. So the multiplayer experience needs to be really tight, while the solo play experience doesn't have to be that tight in that sense.

But if we restricted ourselves to the multiplayer units [in single-player], we would ultimately lose a lot of gameplay. We've got a lot of tools that we're going to use -- our challenge mode, like our tutorials, like our improved score screen and improved replay screens -- all to try to help players make that transition from solo play to multiplayer so they can acquire the right skills, instead of leaning on something that never really worked with to begin with.