Designing a successful casual game is a matter of balance and precision, and Bejeweled, Zuma and Bookworm creators PopCap are one of the masters of the art, with a projected $170 million in sales in 2008.

So how do they do it? The company has just released Bejeweled Twist, the first major gameplay update to its popular match-three title, and one that significantly changes the way the game is played. 

So on the heels of the game's release, Gamasutra spoke to co-founder and chief creative officer Jason Kapalka about just what separates a "clone" from a true innovation in casual gaming, and how he balances his games to be accessible for his core audience.

Of particular interest is Kapalka's assertion that -- legal issues aside -- there is a "moral/ethical" question about what constitutes originality in the casual space; he also views the creativity issue to be one hardly relegated to that space -- "You can't imagine how World of Warcraft could have existed without EverQuest."

Let's talk about design for Bejeweled Twist. The core mechanic reminds me very much of one of the modes in Super Puzzle Fighter for Dreamcast. Have you played that?

Jason Kapalka: I've played Puzzle Fighter.

You haven't played the mode where you rotate four blocks?

JK: I don't remember that one, no. I wouldn't be surprised... since we've started working on it I've run across a number of games that have the mechanic of rotating things.

In a sense it's like Hexic only with, you know, a square grid rather than a hexagon shape. So I haven't played that one but I'm not surprised.

You should try it. The thing I miss from playing that one when playing this one is being able to rotate the other direction. Why can't I do that?

JK: That is definitely a question that's been asked many times. We certainly tried that. That's one of the first things we did, when we put the game together -- put in an option to rotate the other direction. And the truth of it is, it actually, it doesn't actually make the game better for the majority of people.

Actually, the problem is, at least in this game -- I'm not sure about the Puzzle Fighter game -- it increases the number of possible moves by a dramatic amount, so it slows down the way you play.

You suddenly have a lot more potential moves any time you scan the board, so instead of playing the game in a fast kind of way, it slows you down since you have so much more to consider. You have to consider left, right, left, right.

It's one of those things where, for the average player, it makes the game more difficult, even though it actually theoretically makes it easier, because you have to consider a lot more to play it.

It sounded like a good idea when we tried it, it's the same problem we had with some games like Bejeweled. Technically there's no reason in Bejeweled you couldn't allow people to move jewels diagonally, as well as up and down.

But it's that same problem that it increases the move space by a huge number, and suddenly, for most people, it just makes it a lot slower, and more deliberate of a game -- which for most people, is less fun.

So keeping it like this ends up making for a much faster and more immediate game. The other way becomes too strategic, and slows things down. But hey, certainly you're not the first and you won't be the last person to ask why you can't do that.

Was it turning older players off, or things like that?

JK: Well it wasn't just older players, really, it was really kind of everybody. It was one of those things that sounds like it made perfect sense to try. It was practically one of the first things we put in there.

There was one drawback which is that it would require right mouse button, and that's often a problem, and that is a little bit of an issue sometimes for more casual players; they just don't get that the right mouse button is there.

But really it wasn't even that, the thing was that after we actually tried it, once people started playing it, the fun factor just went down radically, something about it just became less fun. So out it went!

I like that you have an actual little vortex graphic that indicates the direction that the piece is going to go.

JK: Well there's a bunch of other little things we put in the game to try to -- especially if you go through the tutorials and stuff -- there's a whole bunch of things to try and suggest that. We tried as much as we could to help give visual cues as to how it plays.

Because, still, for casual players, it takes a while to get your head around the rotating mechanic, so we wanted to make it as easy as possible to get a feel for it and make it as unthreatening as possible in the earlier levels. Later levels, they can get pretty difficult.

It seems really hard to think that way -- to figure out what will be difficult for casual players. Because to me that's very intuitive, but there was an older lady that was standing next to me at the event, who was playing and she had a hard time.

She didn't really get it, and then someone came over and tried to explain it to her, and she said "I don't want you to explain it to me. I want to read it in the game." He said "Okay, we can go back to the tutorial."

JK: Yeah, if they miss the tutorial it would be harder, for sure. So we try to make it so that the tutorial helps you, but at a certain point you want to go and play around with it. Like when my mom plays it, at first she's just spinning things around and doesn't get it, and then, after a while, she starts to get it a bit more.

She's not great at it, but she starts to understand how it's working, and after a while you start seeing more patterns to it, you start following that, so it definitely has a bit more of a learning curve than basic Bejeweled does.

That's one drawback. I think on the upside it also has a lot more depth than regular Bejeweled has. Once you do learn the mechanic of it, there's an awful lot you can do with that. You see some of the guys over there -- they're quite good.

There's a lot of strategy and interesting things you can do with it that were not possible in Bejeweled. So it's a bit of a tradeoff.

Do you think that a game like Hexic is too complicated?

JK: I don't think Hexic is too complicated.

I mean for, say, the demographic you're targeting?

JK: Not necessarily. The only thing I might have questioned with Hexic is the same thing we had with Bookworm, and that is that I think the mechanic is fine, but there's a little something about hexes that turns people off.

Hexes look like, I don't know, I think they give off a vibe of science, of dirty stuff, of war games, and hex paper, something about them just turns people off.

PopCap's Bookworm

Bookworm is an odd one. I don't know if you've played that one, but Bookworm is a word game; it's basically Bejeweled with letters, if you imagine it that way. It started off as a straight grid, and that didn't work.

We ended up with a hexagonal grid and that played really well, but the problem was anybody who looked at a hex grid just was turned off right away. So we ended up doing something where we kept the hex grid but faked it.

So the hexes got turned into squares, like little tiles, but they're offset by 50 percent. And that's just a cosmetic change, but it actually makes the game much more appealing to casual players.

So I think that's the issue with Hexic. It's not necessarily the game is complex; [the issue is] that it looks repellent in some way because of that weird hex thing. There's something about hexes that's not comforting. I think it's the reason.

Imagine Scrabble if it was a hex board. In theory it could still be a good game, but it would turn off a lot of people.

How much trial and error stuff do you have to do to figure out what casual players are actually going to be able to grab on to?

JK: Well, we do a lot. There's definitely a great deal of testing -- like we mentioned the mom test, where you show it to your mom, but frankly you can do that with anybody.

You can go grab somebody down the hall, somebody from accounting, somebody who doesn't play games, and say "Okay, try this out" and watch how they do it. See what frustrates them, and then try it again later on when you make some changes. We do quite a bit of that.

And at the same time, that only works to some extent. We're still making games that we like to play. At a certain point, you have to just trust yourself that if you like playing it, that other people like playing it.

So you have these testers to find out if you've made some wrong assumptions, if things are not working quite the way you want -- but ultimately, it's really hard to make a game that you don't like and put any passion into it. So I like the game, I enjoy playing it. Hopefully if I like it, other people will enjoy playing it too.

I wonder whether testers or players in an older demographic might be too nice about it, and say that they like it even if they don't, just because they like that you made a nice game.

JK: Of course people will do that stuff. Your mom's not going to criticize it. But you're not looking for that; if you're showing the game to your mom, you don't look to see if she likes it; you look to see if she can understand how to play it, or if she continues to play it when you're not watching, things like that. Certainly we don't just ask for an opinion.

I did actually notice that. I'm here with a friend that actually hasn't played that Puzzle Fighter game that I had played, and it actually did take him a little longer to pick up the mechanic. Having played that game a lot, I understood it right away.

JK: It can take a little time to pick out; that was my main concern with this. We wanted to make sure that for people who take a fair time to pick it up, it's still not too threatening. If you start a game like that where you're still learning, and it's kicking your ass while you're learning it -- that's kind of harsh.

So we tried to make sure that the tutorial and the first bunch of levels are very forgiving, so that you don't feel like you don't want to learn it anymore.

We tried our best to make it easy to get into, so once someone has spent a bit of time with it and does learn it, there's a very good chance they'll dig it. It's how we get over that little initial thing. That is somewhat serious -- you do have to consider that.

How do you know when you have when you have too many mechanics? Because you've got the mines there, you've got the rocks, and the locks.

JK: We took out a number of things. We were pretty considerate; there were a lot of extra things that have been taken out. There used to be ice gems that you could make by forming an X.

When you formed an X of gems, they'd turn into the ice gem. And when you used the ice gem, it would freeze time for a few turns, and all that stuff. It was kind of cute -- but again, along with a bunch of other things it's like "Alright, how much stuff do we need?"

We took out a lot. We tried to keep it down to a reasonable level. There were lots more special power gems that we took out, and so we kept it to the basic fire and lightning.

There are a couple advanced gems you can get, but by the time you get to fruit gems, for example, you've been playing for quite a while and you have to know what you're doing.

There are one or two scary things you see on very high levels, like level 14 or something like that, but again, the theory is by the time someone's good enough to get to that level, they're not going to be intimidated by that.

Do you think you might ever release a Bejeweled Twist hardcore version that had the extra bits back in it, and rotations in both directions?

JK: Oddly, both those things are within the realm of possibility. There's some stuff I'm probably not at liberty to even discuss yet, some possible partnerships with people to do some strange variants of Twist.

Like licensed versions, perhaps?

JK: Collaborations, yeah. Some of those could be in the realm of possibility... strange hybrids, like a Puzzle Quest kind of thing, where there might be some more complex or RPG-based elements attached on to aspects of it.

That'd be nice.

JK: I kind of like some of that stuff. It's one of those things where you have to draw a line at some point and aim more at the casual audience, and so we did restrict some of those things.

I think it'd be good if you made one of those. Most people aren't aware that games like that have been made since 1994 -- Puzzle Quest-type games. There's a Puyo Puyo dungeon game, where you walk around on a world map and then you have random battles like in a traditional RPG, but you play Puyo Puyo.

JK: Well actually, I was aware Puyo Puyo had a lot of variants. I don't think I've played that one.

It never got released in the US.

JK: There have been a few weird variants -- there were occasional ones, Puzzle Quest was certainly the most high-profile one.

It hit at the right time.

JK: Yeah, I think there will be more. We had Bookworm Adventures a year or so before Puzzle Quest, which was not quite the same thing, but it was like the RPG-meets-word game hybrid. The same genre, not quite the same deal. I've seen a couple of Puzzle Quest rip-offs; they haven't been very good.

The new Puzzle Quest is supposed to come out pretty soon.

Puzzle Quest: Galactrix is actually using the hex grid.

JK: That's what I saw -- and you know, for a hardcore crowd, that might be okay, because they might not mind that. They're definitely not going for a casual audience, that's for sure.

No, they're not. And the game also has a space theme, as well.

JK: That sounds so hardcore.

I wonder how audiences who loved Puzzle Quest are going to feel about Galactrix.

JK: In our experience, it depends on what it is. I haven't seen the whole thing. Twist has a very vaguely spacey theme, but you wouldn't call it science fiction.

No, it's more like a Spore-style spacey than it is Battlestar Galactica spacey.

JK: And certainly we've seen that the more hardcore, crunchy sci-fi settings can turn off the casual crowd.

And the female crowd.

JK: So them trying to do that, they may not care. I do know those guys a little bit -- they're pretty hardcore gamers.

They made those Warlords games forever.

JK: It's interesting. They may have started as a "Let's just do whatever we can to make some money [game]". Obviously I think their sensibilities were such that they ended up making something kind of unusual.

Many people talk about Bejeweled clones -- that's a game that obviously had some inspiration from Bejeweled, but certainly is not something that I would have done. And certainly, it's something really cool that I'm glad someone else did. So it's cool to see a game that we did that can inspire someone else to do something really cool.

Within the casual space, I've been having to revise my idea of what a "clone" is, because there's a lot of them. You could describe a lot of PopCap games that way, as well. Like AstroPop and Zuma. Since the casual space has a narrower focus, it seems really tough to know whether you're using a similar mechanic and tweaking it -- which happens all the time in larger games -- or functionally cloning.

JK: We've been accused of ripping off of some games. At the same time, you don't usually hear people saying that World of Warcraft ripped off EverQuest. Or that Half-Life ripped off Quake. The similarities are pretty close; you can't imagine how World of Warcraft could have existed without EverQuest. It's not possible. Or any of games now, without World of Warcraft.

I don't know; it's kind of a tricky thing. Personally, I like if games borrow stuff from our games, then add something new to it. I'm usually pretty happy about that. Puzzle Quest or Jewel Quest, or some other games where they've taken the Bejeweled mechanic and done something interesting with it, I generally feel pretty cool about that.

And I hope that when we do things that are building on earlier game mechanics, that we also at least add something new to it. What sucks is if you make a clone or a derivative game that is worse than the original, and doesn't really add anything.

If you're iterating on it, and adding something that wasn't there before, if it enhances the field of game design, I think that's worth doing. That may be different from what a legal definition would be, but, [it's] the moral/ethical [definition]. If you actually make the game better, you could argue that you have a right to do it.

I was talking to Cliff Bleszinski, the Gears of War designer, and he was upset that people were stealing the roadie run mechanic from Gears of War, but not stealing the active reload mechanic, because he thought that was a really great thing that more people should steal. He wasn't mad that they were taking any of his mechanics, he was just like, "Why didn't you take this one? It was really good!"

JK: We get the same thing too, occasionally, and it is simple things like that, If someone rips off Bejeweled, sometimes they'll do dumb things -- like they won't get the gravity of the gems right, so when they fall down they either fall down really fast, or really slow.

It seems like a simple thing, but it could make a big difference, in terms of how the games feel. That's one of those things where it's like, "Dude, if you're going to rip off the game, rip it off right. Get those things correct."

Early versions of Luxor, when it was still called Giza, had huge issues with playing it, and you'd be playing it and going "the balls feel wrong." They just felt wrong. None of the satisfaction of that "clink clink clink clink" that you get in certain levels there.

There's a lot of that we try to work on. It's just the feedback to make the games feel solid.

That's true for a lot of hardcore games too, like if you look at a lot of the Diablo rip offs and then Diablo, a lot of them, they seem like they should be better, but they just didn't have the little details of the visceral impact of various things. It often is just the little details.

Have you looked at Nintendo's new DSi? It has the ability to download games. It seems very relevant to you fellas.

JK: Well, we are doing some DS games now, but the truth is we're just getting started on the DS right now. We're doing Peggle for DS first and after that, probably we'll see what comes up.

But yeah, the idea of doing downloadable content always seems like a pretty cool thing. It needs to be seen... like the Wii is cool, but WiiWare, I don't know yet; I'm not clear that WiiWare has actually turned out to be as big of a success as they were hoping at this point.

Part of it is just that the Wii is not a great platform for downloadable. Maybe it'll get better, but I'm not sure it will. Whereas Xbox Live obviously has turned out to be a really decent platform for us. So the DSi -- yeah, maybe, it's hard to say.

And part of this stuff is, unfortunately you have to make some decisions about which platforms to pursue and which not to. But maybe. We're definitely doing DS stuff.