Puzzle Games - Analyzing the Design of Bejeweled - Extra Credits

James recently had an aspiring designer come up to him and say, "Man, puzzle games are easy. Anybody could make a Bejeweled clone." He wasn't entirely sure how to respond to that. Saying that making a type of game is easy is something you never want to do as a designer. For one thing, it's a misstatement. Making a good game is always hard, regardless of genre. So, making sweeping statements like that sort of shows a lack of curiosity. Plus, it devalues a lot of people's work, and it demonstrates that you're only examining games on a surface level. James didn't want to be too hard on him because, well, to be fair, this is a rather common attitude out there on the interwebs. So, he sat the guy down and walked him through an exercise that James often goes over with his students at DigiPen. And then we realized, "Hey, we could totally go over that exercise here." So, get yourselves ready. This is the first Extra Credits Practicum. Kind of surprised it took us 74 shows to do one. To get the most out of this episode, especially if you're hoping to get into game design someday, I'm going to strongly recommend that you pause a lot

and do each of these little exercises as they come up. Don't worry, I'll warn you and play a little music when it's time to pause. For the rest of you who don't feel like doing math right now, that's cool. You'll still be able to follow along. Oh, and before we start, I want to give a big shout-out to our friends at PopCap. First, you guys are awesome and you make awesome things. Second, I hope you don't mind me deconstructing one of your games here. All right, so today we're going to go over the web version of Bejeweled 2 because I know everybody can access that for free. You can find it over on the PopCap site. So, if you are participating in today's exercises, go start up a new tab, get it fired up, and load up classic mode. If you've never played Bejeweled before, pause us for 10 or 15 minutes and get the basic mechanics down. We'll wait. First pause starts now. And we're back. Now, the first thing to remember when analyzing a game is that as game designers, we are scientists. We engage in the scientific method. We find a question we want to explore, we form a hypothesis, we test that hypothesis against empirical data, and then iterate

on that hypothesis based on how it fits with the data we've acquired. So, let's start with a question. How does Bejeweled 2's leveling system work? Okay, first we need to form a hypothesis, and then test that hypothesis against the real-world data that you acquire from playing the game. For example, you might guess maybe beating a level is determined by the number of moves you make on that level. When you make enough moves, you progress to the next level. All right, so you got your own hypothesis in mind? Awesome. Now, pause us and go test it out. You back? Cool. So, how did it go? Was your hypothesis correct? You probably found that progressing through levels is actually determined by the player's score. So, now we need to dig a little deeper. Where you're going to try to understand if there's a purpose behind this system. So, the first thing we're going to do is establish how many points does it take to complete the introductory levels. So, it's time to collect some data, i.e., play some games. Pause this, go beat the first six stages, record your score, and come back. Go.

All done? Great. So, now to those scores. I'm going to do something here you should never actually do, and I'm going to round these numbers a bit to make the math easier for the show's sake, but you should never do that. Bad designer. No. All right, on to the numbers. To beat level one, it takes 500 points. To beat level two, it takes 1,500 points. To beat level three, it takes 3,000 points. Level four takes 5,500 points. Level five, 8,800 points. And level six, 13,200 points. Now, a designer should always be thinking about how the player experiences the game. So, how does the player experience those numbers? What would we have to do to our current data set to make it more accurately represent the player's experience? Well, the player rarely starts at level one thinking, "Oh man, only 13,200 more points till I reach level seven." No, no, no, no. They spend much more of their time thinking, how long until I beat this stage? So, we're going to have to take the difference between each level value to see how long it takes to

get from one level to the next. Much more useful than simply looking at raw point values required to get to a given level. So, pause, do the math, and come on back. You got it? Here's how the numbers should break down. It takes 500 points to get from level one to level two. It takes 1,000 points to get from level two to level three. 1,500 points to go from level three to level four. Then 2,500 points from four to five. 3,300 points from level five to level six. And to get from level six to level seven takes 4,400 points. Okay, so now that we know how many points it takes to get between the first few levels, we can see it gives us a sort of weird slow exponential curve. But now what? How do we make this data useful? Well, let's return to the player. What other system affects how the player experiences this system? Well, of course, the scoring system. So, now we have something else we need to get data on. How many points does matching three gems on any given level earn you? How about matching four gems on any given level? How about matching three gems and chaining into

another set of three? Pause, grab some data, come on back. You got it? Awesome. So, matching three gems at level one will give you 10 points. Matching three gems at level two will give you 15. Matching three gems at level three gives you 20 points. Then 25 points, 30 points, and at level six it gives you 35 points. And we see that all other block combinations simply give a multiplier to this match three base score. So, how does the player experience the conjunction of these two systems? To put these two systems together, we're going to have to divide the amount it takes to get to the next level by the amount of points that a base match three will get you on any given level. Now, you may ask why we're doing that. What will the number we get out of that mean? If you guessed it'll define how hard a level is, you're dead on. But, there's another important variable here. What helps define difficulty? Your losing condition. And in Bejeweled 2 classic mode, what's the losing condition? When you can't make any more moves. Also worth noting is that at the beginning of every level, the board is shuffled. I'll leave it to you guys to piece out why on average

making a valid move in Bejeweled leaves fewer total valid moves on the board. But, just assuming that's the case, the number we've now come to, the amount of points to progress to the next level divided by the base points on the given level, tells us directly, numerically, how challenging we can expect a given stage to be. What's amazing about this system is the level of control over the difficulty it gives to the designer. You can see it right there in our initial data set. PopCap took a vaguely exponential set of numbers, used a completely linear number set to smooth out that exponential curve, and then tweaked the numbers wherever playtest told them that players were having a hard time or not being challenged enough. For example, if you've been doing all the math with us up to this point, you may have already noticed that the increase in difficulty from level 3 to level 4 is much greater than that from level 4 to level 5. This relatively complex system is totally invisible to the player. To them, it simply feels like they're progressing, since the system is built to continuously increase the amount the player is rewarded and make them feel empowered without breaking the difficulty curve. In fact, it's this system that let the designers construct Bejeweled's carefully honed challenge curve. But, this entire system is dependent on the lose condition and the board reshuffling at every new

level. A slightly lazier designer who didn't shuffle the board between rounds would have created a totally different and probably inferior game. And the really incredible thing is that you'll see players who played a lot of Bejeweled, no matter how casual, no matter how uninterested in strategic thinking, playing around with this system. Ask any long time Bejeweled player, and they'll tell you not to use your special gems until you need them, since they carry over between levels. But, if you ask them why, they'll probably tell you, "Oh, well, because it's better." Without a word about all the math going on under the hood. But, the math ensures that that's the way things work, and it also ensures that they get a sense of that through playing. Also, if you really want to know how deep this rabbit hole goes, answer me this: How much harder is it to make your first match on level 5 as compared to level 1? That's correct, no harder at all. But, your reward for doing so is vastly increased. This system is even designed to make you feel like a badass every time you get to a new level just by the way they combine their point system and their lose condition. So, you can see the depth of thinking that goes into making a good game, puzzle game or any other kind. The next time you hear somebody trying to claim that building little puzzle games like this is simple, you will know better. And just for the

masochists out there, here's a little easy homework assignment for you. See if you can figure out what they changed in Bejeweled 3 or the Facebook version of Bejeweled, and then see if you can figure out why. If you're ever feeling stumped, just come back to the golden question. How does the player experience this? Well, that about does it for us this week. The three of us are going to take the next couple weeks off to rest and spend some time with the family for the holidays. We'll be back to our regular weekly schedule starting January 11th. If you're planning to attend MAGFest, James and I will see you there. To everybody else, have yourselves an awesome holiday. See you soon. Dreamer. Hold on just a little longer. The sun's not far from here rising. And this is the day that we we have all been waiting for.

Hey, dreamer. Hey, dreamer.