How did you approach writing material for Torchlight, which had to clearly reference Diablo without simply rehashing it?

MU: It was a little tricky, just because the games do have so many similarities that it's hard not to make a lot of the same choices. I really couldn't judge if I was successful. I'm sure some people found the music way too derivative and referential to Diablo, and other people didn't feel that way.

But it was really different to just sit down at the piano. I tried to write a relatively strong basic melody first, so hopefully that makes it significantly different. The actual melodic structure is actually a lot more conservative than [Diablo's] Tristram in some ways. It's more of a traditional progression and melody.

Diablo struck me as relentlessly textural -- it's a constant wash over you, putting you in that world, as the bassline melody travels to the different instruments. Torchlight feels more optimistic, evoking more of a fairy tale feel.

MU: Yeah. There's not the big doomy melody that I drive into the ground all through Diablo. But that worked well for the Diablo series. That thematic material tied in from the original Diablo all the way to the Lord of Destruction [expansion pack] music. I'm sure you'll see the return of that theme in what Blizzard's up to now [with Diablo III]. That will be interesting to see.

How conscious are you that there's someone out there working on Diablo III who is tasked with living up to this thing you've created?

MU: Well, I'm aware of it, but I think that that team definitely has all the talent they need to get the job done right. I'm good friends actually with Joseph Lawrence, who is doing a lot of the audio work. I'm looking forward to it being its own distinctive thing.

You know, I'd really love to hear Joseph's ambient music out there more. I hope they don't feel they need to be too influenced [by my music], and that they are free to do their own thing, because the gamer in me thinks that would be more entertaining.

One of the tracks they use is a new recording of your theme, with a much heavier orchestral treatment.

MU: Well, I think you can't necessarily assume that a promotional track is going to function as an in-game track.

Similarly, I was speaking to [Runic co-founders] Max and Erich [Schaefer], and they were saying how strange it was to be showing Torchlight at PAX last year, and then across the hall seeing this huge Diablo III banner.

MU: I'm sure it will be great. It will be interesting in the next few years to see how viable single-player is as a genre. That's the real challenge. I think Torchlight was so successful because we marketed it so cheaply, and we depended on the good will of any potential pirates out there -- you know, keeping the DRM on the light side, and trying to make it easy and convenient. That seemed to be relatively vindicated.

But it's hard to do that with a big game. Blizzard may be one of just two or three companies that can really do a viable single-player game and doesn't need to monetize it beyond the box. It's really hard. The more you go from a $5 download to a $50 box, the harder it is for the average player to resist the temptation to grab it from a torrent. That's the dynamic you have to fight with.

Of course, the math doesn't always pencil out. If you want to spend $10 million or more developing a game with that level of content, you can't really have the pricing scheme we had for Torchlight. Torchlight was really only successful in the context of the time and the money that went into it.

It's a shame. I feel, in a lot of ways, it's a bit like the Busby Berkeley era -- you know, the big MGM musicals that had their day, and those old big bands that used to barnstorm across the country with 20 or 30 pieces.

The era of huge productions.

MU: Yeah. And then the economics changed. The fashion and the economy of the whole thing conspired to end that era. I mean, I don't really stay up at night worrying about it, but I feel like I got to see the glory years of the single-player game as a genre, and the economics are conspiring against it right now.

It's a shame, because I think people really enjoy it. I know do, having the ability to just buy a single-player box or download one thing. It's about having the idea of a game being a self-contained universe that you don't need to get fresh content for all the time. It's a certain kind of experience. It will be interesting in the next few years how publishers deal with that.

Well, even you guys are making an MMO next.

MU: Yeah, but it's, you know... [laughs] Hopefully, we just get to keep on making games for the next few years with that team, at least. That's all we're looking for.