Game Design: Theory & Practice Second Edition: 'Interview with Jordan Mechner'

The following excerpt comes from Richard Rouse III's book Game Design: Theory & Practice, which has just been released in a thoroughly revised and expanded second edition. The book covers all aspects of game design, from coming up with a solid idea to creating the design document to implementing the gameplay to playtesting the final game. The book also explores the craft of game design through in-depth interviews with some of the field's most experienced and successful game designers. The interview subjects include Sid Meier, Ed Logg, Steve Meretzky, Chris Crawford, Jordan Mechner, Will Wright, and Doug Church. Below is an excerpt from Mechner's particularly thorough interview, covering his superb but overlooked The Last Express, as well as his most recent triumph, Prince of Persia: The Sands of Time.

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The only complaint one could have about Jordan Mechner's work in computer games is that he has not made more of them. Each of the games he has designed and spearheaded - Karateka, Prince of Persia, and The Last Express - has had a unique elegance and sophistication that one seldom finds in the world of computer games. But the game industry has had to do without Mechner for several periods of time while he pursued his other great love, filmmaking. Indeed, it is Mechner's knowledge of film that has helped to contribute to the quality of his games. But this quality does not come through the epic cut-scenes and barely interactive game mechanics that so often come about when developers attempt to merge film and gaming. Instead, Mechner has blended film and game techniques in unique and innovative ways, helping his titles to tell stories visually while still retaining the qualities that make them great games. This is the most apparent in his most recent work, the amazing Prince of Persia: The Sands of Time.

As far as game design, it seems that Prince of Persia was a logical extension of what you did in Karateka, and Prince of Persia 2 was in turn an extension of that. But The Last Express seems to be off in a completely new direction. What provoked you to do something as different as Last Express?

I guess I don't think of Last Express as being off in a new direction. I was still trying to tackle the same problem of how to tell a story and create a sense of drama and involvement for the player. There are a number of proven action game formulas that have evolved since the days of Prince of Persia. Part of what interested me about doing an adventure game was that it seemed to be a wide open field, in that there hadn't been many games that had found a workable paradigm for how to do an adventure game.

So it wasn't the inspiration of other adventure games?

No, on the contrary in fact. If you look at the old Scott Adams text adventures from the '80s, it's surprising how little adventure games have progressed in terms of the experience that the player has: the feeling of immersion, and the feeling of life that you get from the characters and the story. So I guess it was the challenge of trying to revitalize or reinvent a moribund genre that attracted me.

What inspired you to set the game on the Orient Express in 1914?

	The Last Express

In computer game design you're always looking for a setting that will give you the thrills and adventure that you seek, while at the same time it needs to be a constrained space in order to design a good game around it. For example, things like cities are very difficult to do. A train struck me as the perfect setting for a game. You've got a confined space and a limited cast of characters, and yet you don't have that static feeling that you would get in, say, a haunted house, because the train itself is actually moving. From the moment the game starts, you're in an enclosed capsule that is moving, not only toward its destination - Paris to Constantinople - but it's also moving in time, from July 24th to July 27th, from a world at peace to a world at war. The ticking clock gives a forward movement and drive to the narrative, which I think works very well for a computer game.

The Orient Express, of course, is the perfect train for a story that deals with the onset of World War I. The Orient Express in 1914 was the "new thing"; it was an innovation like the European Economic Community is today, a symbol of the unity of Europe. At the time it was possible to travel from one end of Europe to the other, a journey that used to take weeks, in just a few days, without trouble at the borders and so on. On that train you had a cross-section of people from different countries, different social classes, different occupations - a microcosm of Europe in one confined environment. All these people who had been traveling together and doing business together, found themselves suddenly separated along nationalist lines for a war that would last four years and which would destroy not only the social fabric but also the very train tracks that made the Orient Express possible. To me the Orient Express is a very dramatic and poignant symbol of what that war was all about. And a great setting for a story.

So would you say your starting point for Last Express was: "I want to make an adventure game; what sort of story can I tell in that form?" Or was it: "Here's a story I want to tell; what type of game will allow me to effectively tell it?"

Definitely the latter. Tomi Pierce [co-writer of The Last Express] and I wanted to tell a story on the Orient Express in 1914 right before war breaks out: how do we do that? I didn't really focus on the fact that it was a switch of genre from Prince of Persia or what that would mean for the marketing. It just became apparent as we worked out the story that given the number of characters, the emphasis on their motivations and personalities, the importance of dialog and different languages, that what we were designing was an adventure game. I consciously wanted to get away from the adventure game feel. I don't personally like most adventure games. I wanted to have a sense of immediacy as you're moving through the train, and have people and life surging around you, as opposed to the usual adventure game feeling where you walk into an empty space which is just waiting there for you to do something.

Was this your reason for adding the "real-time" aspect to Last Express, something we're not used to seeing in adventure games?

Of course, it's not technically real-time, any more than a film is. The clock is always ticking, but we play quite a bit with the rate at which time elapses. We slow it down at certain points for dramatic emphasis, we speed it up at certain points to keep things moving. And we've got ellipses where you cut away from the train, then you cut back and it's an hour later.

But still, it's more real-time than people are used to in traditional adventure games.

Or even in action games. I'm amazed at the number of so-called action games where, if you put the joystick down and sit back and watch, you're just staring at a blank screen. Once you clear out that room of enemies, you can sit there for hours.

You mentioned filmmaking back there, and I know in 1993 you made your own documentary film, Waiting for Dark. Did your experience with filmmaking help you in the making of Last Express?

It's been extremely helpful, but I think it can also be a pitfall. Film has an incredibly rich vocabulary of tricks, conventions, and styles which have evolved over the last hundred years of filmmaking. Some have been used in computer games and really work well, others are still waiting for someone to figure out how to use them, and others don't work very well at all and tend to kill the games they get imported into. The classic example is the so-called "interactive movie," which is a series of cut-scenes strung together by choice trees: do this and get cut-scene A and continue, do that and get cut-scene B and lose. For Last Express, I wanted the player to feel that they were moving freely on board a train, with life swirling all around them and the other characters all doing their own thing. If someone passes you in the corridor, you should be able to turn around, see them walk down the corridor the other way, and follow them and see where they go. If you're not interested, you can just keep walking. I think of it as a non-linear experience in the most linear possible setting, that is, an express train.

All of your games have featured cut-scenes in one way or another, and in Karateka, Prince of Persia, and Last Express they've all been integrated into the game so as to be visually indistinguishable from the gameplay. Was this a conscious decision on your part?

	The Last Express

Absolutely. Part of the aesthetic of all three of those games is that if you sit back and watch it, you should have a smooth visual experience as if you were watching a film. Whereas if you're playing it, you should have a smooth experience controlling it. It should work both for the player and for someone who's standing over the player's shoulder watching. Cut-scenes and the gameplay should look as much as possible as if they belong to the same world. Karateka used cross-cutting in real-time to generate suspense: when you're running toward the guard, and then cut to the guard running toward you, then cut back to you, then back to the shot where the guard enters the frame. That's a primitive example, but one that worked quite well.

Same idea in Last Express: you're in first-person point-of-view, you see August Schmidt walking toward you down the corridor, then you cut to a reaction shot of Cath, the player's character, seeing him coming. Then you hear August's voice, and you cut back to August, and almost without realizing it you've shifted into a third-person dialog cut-scene. The scene ends with a shot of August walking away down the corridor, and now you're back in point-of-view and you're controlling it again. We understand the meaning of that sequence of shots intuitively because we've seen it so much in film. A classic example is Alfred Hitchcock's Rear Window. The whole film is built around the triptych of shot, point-of-view shot, reaction shot, where about half the movie is seen through James Stewart's eyes. That's the basic unit of construction of Last Express in terms of montage.

I thought one of the most innovative design elements in the game is the save-game system you used. Players never actually save their game, but Last Express automatically remembers everything they do, and they can "rewind" to any point in their game they want, if they want to try something a different way. How did you come up with this system?

I'm glad you asked. I'm very proud of the save-game system. The funny thing is that some people, including some reviewers, just didn't get it. We still occasionally get a review where they say, "It's too bad you can't save your game." Our goal, of course, was an extension of the design philosophy that went into the point-and-click system; we wanted it to be very simple, very transparent, and intuitive. To have to think about the fact that you're on a computer, and you have to save a file, and what are you going to name the file, and how does this compare to your previous saved game file - to me that breaks the experience. The idea was that you'd just sit down and play, and when you stopped playing, you could just quit and go to dinner, or use the computer for something else, or whatever. And when you go back to playing, it should automatically put you back to where you left off. And if you make a mistake, you should be able to rewind, like rewinding a videotape, go back to the point where you think you went wrong, and begin playing from there. And I think it works. The six different colored eggs were inspired by, I guess, Monopoly where you can choose which piece you want: the hat, or the car... The idea was that if you have a family of six, everybody will have their own egg, and when someone wants to play they can just switch to their own egg and pick it up where they left it off. People who complain that you can only have six saved games, or that you have to use colors instead of filenames, are fixated on the conventional save-game file system; they've missed the point. An egg file isn't a saved game; it's essentially a videotape containing not just your latest save point, but also all the points along the way that you didn't stop and save. You can usually rewind to within three to five real-time minutes of the desired point.

Again differing from many other adventure games, Last Express offers a fairly non-linear experience for the player, where there seem to be multiple ways to get through to the end. Do you think non-linearity in adventure games is important?

	The Last Express

It's crucial; otherwise it's not a game. There are a couple of game models which I wanted to steer away from, one of which is where you have to do a certain thing to get to the next cut-scene or the story doesn't progress. Another is the kind of branching-tree, "Choose Your Own Adventure" style, where there's ten ways the story can end, and if you try all ten options you get to all ten of them. One of the puzzle sequences that I think worked best in Last Express is one of the first ones, where you encounter Tyler's body and you have to figure out what to do to get rid of it. There are several equally valid solutions, and each one has its own drawbacks, ripple effects down the line. For example, if you hide the body in the bed, you risk that when the conductor comes to make the bed he will discover the body there, so you have to deal with that somehow. You can avoid that problem by throwing the body out the window, but if you do that, then the body is discovered by the police. And they board the train at the next stop and you have to figure out how to hide from the police when they're going compartment to compartment checking passports. Either way, your actions have consequences on the people around you. As another example, if you throw the body out the window, you may overhear François, the little boy, saying to his mom, "Hey, I saw a man being thrown out the window." And she'll say to him, "Shut up, you little brat, don't tell lies!"

I hadn't even noticed that.

The game is full of little things like that.

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So is that why you don't tend to like other adventure games, because they're too set in "primrose path" style?

Some adventure games have great moments, but in terms of the overall experience it's rare that a game consistently keeps that high a level. In Last Express too, there are parts of the game that don't quite live up to the expectations set up by that first disposing-of-the-body puzzle. Defusing the bomb is one I wasn't so happy with. You just have to grit your teeth and follow the steps; there's no way around it. It's not a particularly clever puzzle. But again, the main concern was that the story would work overall, and that the overall experience would be satisfying.

I've heard many adventure game designers say that to effectively tell a story, you really need to limit the player's options and force them on a specific path. Do you agree with this notion?

It's true, of course; it's just a matter of how you limit what the player does. The too-obvious-to-mention limit in Last Express is that you can't get off the train. Any time you get off the train, the game ends. The only way to win is to stay on the train all the way to Constantinople. So in that sense, yeah, it's the ultimate linear story. You're on a train, you can't get off. But given that, within the train you should be able to move around as freely as possible. There are some doors that we just had to close because they would have changed the story too much and they wouldn't have let us get to the ending we wanted to get to. What if you take the gun and go through the train and kill everyone? We decided you just can't do that. So there's definitely a trade-off. The more wacky, off-the-wall options you give the player, the more that limits the complexity and the power of the story you've set out to tell. Whereas if you want to keep a very ambitious, central narrative that's itself large in scope, then you have to start closing doors around that, to make sure the player stays in the game.

Every game approaches this challenge in a different way. With Last Express, the train motif gave us the metaphor that we needed to keep it on track. I think once people get the idea that they're on the train, time is ticking, and they have to do certain things before certain stops, and they have to get to Constantinople or else they haven't really made it to the end of the line; once they get that, the story works. It's a matter of finding a balance for what works for each particular story. What's right for one game might not be right for another. I wouldn't even begin to know how to use the Last Express engine to do a game that wasn't set on a train.

How did Prince of Persia: The Sands of Time come about and how did you get involved with the project?

In 2001 Ubisoft approached me with the idea of bringing back Prince of Persia and doing a new game for consoles. I went up to Montreal to meet Yannis Mallat who was the producer of the project and the small team that he'd assembled.

Had they already started development?

	Prince of Persia: The Sands of Time

It was actually kind of interesting the way they started. They showed me some AVIs that they had done in the couple of weeks before. These were really quick AVIs. They didn't focus on the look of the world or any graphic kind of bells and whistles. They were very crude, and had an animated character running up a wall, jumping onto a ladder. Just very quick little demos of the kind of gameplay they had in mind. The great innovation that was already apparent was here was a guy who could run on walls. So they'd really taken the dynamic of Prince of Persia 1, which was a 2D side-scroller, and brought it vertically into a third dimension. Which was something I hadn't seen done in any Tomb Raider style action-adventure game. It was just a brilliant idea that opened up a whole world of possibilities as to how this game could capture the excitement of the old-time side-scrollers in a modern real-time 3D game. So based on that we made the deal for Ubisoft to go ahead and start this project. My involvement increased. I had originally thought I would just be a consultant on the project, but I came on board to write the story and the screenplay, and once I'd done that I ended up directing the actors in the voice recording, and finally joined the project full time as a game designer. I was commuting between L.A. and Montreal and my trips kept getting longer and more frequent until for the final stage of the project I moved up to Montreal with my wife and kids. That was the last four months, the summer of 2003.

So you were sucked back into game development against your will?

That's a good choice of words. [laughter] The other word I would use is seduced. It was just such a fun project and the team was so talented and working so hard and the potential was so clearly there from the beginning. They wanted to do something really extraordinary. Ubisoft Montreal was not yet on the map then the way they are now, following Splinter Cell and Sands of Time. At the time this team had not yet done those types of high-profile games but they were certainly capable of it. They just had to prove it to the world. It was a very refreshing atmosphere; working with them was a real pleasure.

It's interesting that Sands of Time is so radically different from the prior 3D incarnation of the game, Prince of Persia 3D.

	Prince of Persia: The Sands of Time

That was one of the first things that I talked about with Ubisoft when they proposed doing a new Prince of Persia game. Neither of us wanted to do another Prince of Persia 3D. So we kind of mutually reassured each other that that wasn't what we had in mind. The problem with Prince of Persia 3D from the moment it was proposed and on through the early stages, the obvious question to ask was, "Isn't this just Tomb Raider with baggy pants and a turban?" And ultimately I think in the end it really was Tomb Raider with baggy pants and a turban. That wasn't enough. So for Sands of Time, Ubisoft and I basically said let's not even look at Prince of Persia 3D. Let's look at the original titles - why were they fun, what aspects of that make us think that a remake now is worth doing? What are the aspects that we want to try to capture from the original? In what ways is this going to be a totally new and different game? Sands of Time, in many ways, was like doing an original title. It had been so long since Prince 1 and 2, ten years, the expectations of what a video game should be are so different now. There was no possibility of literally sticking to the rules of gameplay or the character or the story or anything like that. We needed a new character, new story, new gameplay, new rules.

Prince of Persia ultimately represented a style of game, a kind of feeling that you get playing it. One of the main inspirations for Prince 1, back in 1986 when I started to program it on the Apple II, had been the first ten minutes of Raiders of the Lost Ark. The idea of doing a game that would have that kind of running, jumping, seat-of-your-pants improvising these acrobatic responses to a dangerous environment. And then of course the story being a swashbuckling adventure movie in the spirit of Raiders, and before that the films of Errol Flynn and Douglas Fairbanks in the '30s. So all of that was also an inspiration for Sands of Time. But when you get down to the details of what can the game character do and how do you control it, we didn't feel compelled to follow the rules that had been set up in the ten-year-old 2D side-scroller. And I think that was all to the good.

To take one example, potions: you find a potion, you drink it, it restores your strength. That was fine in Prince 1, but wouldn't work in the new game. Because why would you have useful magic elixirs sitting around in a dungeon, waiting for someone to find them and drink them? Why wouldn't they have been drunk already by a thirsty guard or prisoner? In a 1989 2D side-scroller, you can assume a certain suspension of disbelief. But when you have a realistic environment that's lavishly rendered with all the painterly beauty and lighting effects and so on that the PS2 or Xbox are capable of, it just doesn't make sense. Ultimately we went with the concept that water itself is the substance that revives you. Water is a natural feature of Islamic and Persian palaces and gardens. You've got fountains and waterfalls. That was a way to take a feature of the environment and make it useful and important for the gameplay. So any place you find water in the game, even if you're standing in a pool, if you drink, it restores your strength. That's one example. If you've played Prince 1 and Sands of Time, you can see that when you get right down to it, nearly every game feature is different. It's just the overall feeling, the spirit, that has been preserved.

The dagger is a really nice element in the game, because it is really important both to the gameplay and the story. Did that start out as a gameplay mechanic or a story device?

Rewinding actually started out as a gameplay wish from creative director Patrice Desilets. When you die and have to restart, you kind of break the spell of the player's involvement in the game. Patrice thought rewinding would be a nice, organic way to allow the player to continue to play uninterrupted, without dying so often. That then gave rise to an engineering challenge, which was "Can this be done on the PS2, on a console system that doesn't have a hard drive?" The engineers worked on that for a while and ended up proving that it could be done. So it was a gameplay idea that gave rise to an engineering innovation that then led to the story question of "How do we justify the player having this ability?" and to the concept of the dagger and the Sands of Time.

The Sands of Time serve a number of functions in the story. First of all, they're the substance that enables you to turn back time. As the player, you have to find ways to collect the sand, and then as you turn back time you use it up. Second, the way that you collect the sand is by killing these sand creatures that are possessed by the sand. They're like undead monsters in the sense that you can hit them as many times as you want with your sword, but the only way to get rid of them for good is to use the dagger to retrieve the sands that possess them, then they disintegrate. So the sand gives you an incentive and a reason to want to fight these enemies. All the other powers of time - being able to freeze your enemies, move at hyper-speed, the sand vortex that when you enter it gives you a glimpse of what's to come - came out of trying to take the central idea and weave it through as many aspects of the game as possible, while keeping the story as clean and simple as possible.

The storytelling in Sands of Time is very elegant, but the plot is actually quite simple. Do you think that more games should strive for streamlined plots? Or was that just something that Prince of Persia specifically called for?

It's a good thing for a game to be as simple as it can be. But depending on the type of game, it calls for a different kind of simplicity. The complexity in Sands of Time should come out of the acrobatics, the nuts and bolts of how do you get through this room. Do you grab on to the pillar and then jump on to the platform, or do you run on the wall and swing on the bar? Those are the kinds of issues that should absorb the player. So the story shouldn't be distracting them with things that have nothing to do with the gameplay. The cut-scenes in Sands of Time are relatively brief and tend to contain the same kind of action that's in the game. In the game you're doing acrobatic action and fighting monsters. So that's mostly what you're doing in the cut-scenes as well, with the occasional brief shouted line of dialog. The conversations that you have with the female sidekick character, Farah, are very much in the midst of this action, this relationship that's being developed very quickly under fire and under pressure. We're not cutting away to another place to have big dialog scenes between characters that we've never met before. The two biggest cut-scenes in the game are the one that launches the story, when the prince actually uses the dagger to open the hourglass to release the Sands of Time, effectively opening Pandora's box, and then one at the end that resolves it. The premise of the story has a dark element, in that the hero himself causes the catastrophe that makes it necessary to play the game. So all of that dovetails very nicely.

Though you kept the story in Sands of Time fairly simple for a modern action-adventure, in terms of the previous Prince of Persias or Karateka it is quite a bit more complex. For example, the prince never spoke before, and the cut-scenes were much shorter and more infrequent.

Prince 1 and Karateka were like silent movies. Silent movies didn't have dialog; they had title cards. Nowadays, with the level of sound and graphics that we're accustomed to, we expect that characters will talk, unless there's a story reason why they can't talk, as in a game like Ico where they don't share a common language. But here you've got a king, a prince, and a princess; you're not going to get away without defining their characters and their personalities to a certain extent. So it's really more a matter of creating a story and dialog, both in the cut-scenes and in the game action itself, that will develop the relationships among the characters and advance the story while entertaining the player.

Also in contrast to the previous Prince of Persia games, which as you mentioned earlier prided themselves on having fairly simple controls, this new one is really quite complex, with all of the different moves the prince can pull off with his multiple weapons, and so forth. Was this done to bring the gameplay up to modern expectations?

	Prince of Persia: The Sands of Time

That's de rigueur for the genre. It's not a handheld game that you play on your cell phone, it's not a point-and-click game like Last Express; this is a console action game, and your audience is going to be people who like to pick up a controller and play. However, within that, I think we did a pretty good job of keeping the controls simple and consistent. We didn't have the kind of semi-arbitrary memorized combinations where you have to hit X-X-Triangle-Circle. Each of the four action buttons does a fairly simple, understandable thing, and from that is generated quite a lot of richness as to what the player can actually do. And that comes from having the controls be context-sensitive. So that, for example, pressing X if you're clinging to a pillar will cause you to eject from that pillar, whereas if you press X when you're standing on the ground, it will make you roll or it will make you jump, depending on the situation. In Sands of Time, it's the same principle as in Prince 1: our goal was to get the player to the point where he doesn't have to think about what button is he going to press, but just develop that instinct of reaching for a certain button in certain types of situations and have the richness flow out of that.

Prince of Persia: The Sands of Time seems to be pushing forward and innovating the storytelling/gameplay blend that's very popular these days. How do you see that evolving in the coming years?

Certainly story is becoming more appreciated as an element of games. But games are not about story. A movie is about the story, a game is about the gameplay. A good story can enrich a game, it can add to the pleasure, in much the same way that a good musical score can add to the enjoyment of a movie. But game designers can sometimes fall into the trap of developing a really complex story and thinking that somehow makes the game more complex or more interesting. Most action/adventure games with complex stories suffer from a clunky alternation between gameplay and cut-scenes. My personal preference to enhance the story aspect of action games is to bring the story into the gameplay. If an interaction can happen while you're playing rather than while you're sitting back and watching a cut-scene, then that's the best place for it. Sands of Time does that to a degree in the relationship between the prince and Farah. As they're fighting off monsters they shout to each other, they call warnings to each other, and occasionally if the prince is hurt after a fight, Farah will express concern. There's a lot of natural opportunities for humor, whereas humor in a cut-scene can seem kind of forced. The times that we do stop the game for a cut-scene between the prince and Farah are actually pretty few and brief, and those scenes focus on significant plot twists that flow out of the gameplay and then right back into it with changed stakes.

Do you hope to one day get rid of the cut-scenes entirely?

	Prince of Persia: The Sands of Time

Oh absolutely. The more we can create a seamless experience where the story unfolds through the gameplay, the more convincing that world becomes. When you bring the story out of the cut-scenes and into the gameplay, the gameplay then becomes more cinematic. In Sands of Time, the camera is not just glued behind the prince's head, following him around. Sometimes you enter a room and the camera takes a cinematic approach, showing you the environment, emphasizing certain features, directing your attention to certain clues. During gameplay, the camera will cut from one angle to another for a dramatic introduction of enemies, to show the prince unsheathe his sword to fight, to show what Farah's doing. As the game camera becomes smarter and freer, that allows you to do things in the game that previously you could only have done in cut-scenes.

I've heard a lot of people say that film was the dominant art form of the 20th century, and now games are going to dominate the 21st century. As someone who's worked in both games and film, I wondered if you wanted to comment on what you think of the future of the two mediums.

I don't know. I sort of scratch my head about that type of statement. Is film more dominant an art form than music? What does that really mean? I think film and video games are very different art forms. We're going through an interesting period right now where video games are more like movies, and movies, or at least a certain type of summer blockbuster movie, are more like video games than they have been at any time in the past. There's a great interest in Hollywood and the video game industry of creating these kind of cross-marketed properties so that you can have the hit movie and the hit video game and the hit theme park ride all come out at the same time. But that doesn't mean that every single film that's made has to be a summer popcorn movie. It also doesn't mean that every video game that's made has to be this sort of spectacular, story-driven, film-friendly thing. The extreme example of a game that has no movie potential is something like Tetris. It succeeds purely as a game. The gap between Tetris and Krzysztof Kieslowski's Blue is pretty huge. [laughter] So there's plenty of healthy room for innovation in both fields, and that's not going to change any time soon.

Jordan Mechner Gameography
Karateka, 1984
Prince of Persia, 1989
Prince of Persia 2, 1993
The Last Express, 1997
Prince of Persia 3D, 1999 (Consultant)
Prince of Persia: The Sands of Time, 2003

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This article is excerpted from Game Design: Theory & Practice Second Edition (ISBN # 1-55622-912-7). For more information about the book, please visit http://www.paranoidproductions.com/gamedesign.

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