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Balancing a game is tricky business. Balancing a multiplayer game is nearly impossible. Balancing a competitive multiplayer game that goes on to be very popular—well that actually is impossible…unless the game has no variety.

The first lesson is that “variety” and “balance” are inversely proportional; the more you have of one, the less you're likely to have of the other. Both sides in chess have identical pieces, and the only difference between the black side and white side is that white goes first. Street Fighter would be much more balanced if we just removed all the characters except Ryu. Quake is fairly “balanced” since each player has the same “moves” (or ability to acquire weapons and armor) as any other player. The different spawn points do introduce some “imbalance” though. The trick is to introduce variety, yet keep a reasonable level of balance. And it’s quite a trick, indeed.

Look, it's perfectly balanced!

What I’ve just described is a very narrow way of thinking about this mysterious concept of “balance.” After all, if the only way to dominate a Quake match were to use the rocket launcher, then how balanced a game would that be? Even if all players had equal access to the rocket launcher, it would be hard to call a game so skewed towards one thing “balanced.” We need a definition of balance if we are to going to talk about it. Let’s give that a shot.

That was quite a mouthful. It basically means that game doesn’t degenerate down to a very small number of real options. This is a pretty broad definition since it encompasses the concept of “brokenness” as well. If, in chess, only pawns were used in tournament play (if pawns were so good as to be “broken”), I would say the game lacks balance, even though both players start with the same pieces. Another point of contention might be my use of the phrase “large number” rather than “large percentage” of viable options. Let’s use my favorite example of Marvel vs. Capcom 2 to explain that.

Whether MvC2 is anything close to balanced is an incredibly complicated question that we’ll have to come back to. For now, let’s say that most players agree that there are about 10 “top tier” characters in the game. Certainly no more than 15. Yet the game offers a whopping 54 characters! Although percentage-wise, that’s pretty poor, I’d have to say that 10-15 characters that are all extremely viable for tournament play is pretty darned good for a fighting game…even if the batting average of playable characters if low. Others might care more about the percentage, but it’s a minor point. Let’s move on to a major point.

Balancing a competitive multiplayer game is orders of magnitude harder than balancing a single player game. When we try to balance a single player game, we are basically striving to match the “skill” of the computer to the skill of the player. There are many techniques for doing this, and there is a large margin of acceptable error. For example, consider what happens if Joe Hardcore figures out a super sneaky way of beating almost every enemy in a single player game for free. Further suppose that this method is very obscure and discovered by less than 1% of all players. Factoring in strategy guides and the internet, sure, others will figure out this method, but the overall impact will be small. Joe Hardcore feels full of himself, the computer doesn’t mind being beaten, and most players will never know about this method at all. It’s bad, but it’s not that bad.

If the same trick/bug existed in a competitive multiplayer game, the game would be totally ruined. The knowledge would spread like wildfire, as the 1% proceeded to crush the masses. The masses would learn the trick, and soon, there would be no gameplay. There would only be the trick. The game would degenerate to the exploitation of a single bug, and possibly the exploitation of another even more obscure bug as a countermeasure to the first. In short, the multiplayer world doesn’t forgive imbalance: it abuses it 100 times more than even many game developers realize.

So how can we make sure that a competitive multiplayer game will be balanced when we release it? Let me tell right now that you can’t. You cannot. There is no way. If your game has the complexity needed to be interesting and successful, then it’s pretty much guaranteed to be beyond the level of complexity that can be fairly balanced right out of the gate. Anyone who thinks otherwise just hasn’t been in the trenches of real competitive gameplay. (Before you send me e-mail, at least read the rest.)

Now that does NOT mean we should give up. And it certainly doesn’t mean the problem isn’t worthy of analysis. There are things we can do to minimize the chances of insane imbalance, and there are methods to correct balance problems when they are discovered. Before we get to those, let’s think about why the problem is so difficult in the first place.

Developers often think they are the best players of their own games. They designed and programmed their games, after all, so they have many advantages. They know the actual equations and formulas the game uses. They know the AI routines. They know the nuances, and the little tricks they put in there. But in reality, the gamers outside the company have many, many more advantages than that. Shall we count the ways?

1) Gamers will uncover any and all relevant equations and formulas about a game through trial and error, testing, and hacking.

2) Gamers will find bugs and “features” that the developers never knew about.

3) Gamers will use features in bizarre ways never envisioned by the developers or even the testers.

4) Gamers have far, far more time to play the game than the developers do. The developers are busy making games, but hardcore gamers have seemingly infinite time. Just look at the EverQuest stats. 85 hours a month was the AVERAGE playing time last year, including people who pay but never log in. Just imagine how much the people at the other end of the curve are playing!

5) The gaming public just has far more pairs of eyeballs than the developers and testers. 1,000,000 people will find something that a team of 30 missed.

6) The developers and testers have skewed perceptions on balance since features change often throughout development. A particular move or strategy might be considered weak, but end up strong. The development team might have a bias against this move or strategy, since they remember it being too weak to bother trying.

7) The developers and testers are often playing without all the options available in the final game, or at least without the final tweaking in place. It’s very possible for entirely new strategies to become viable after new features are added at the last minute or old values are tweaked. Yet the developers often have little or no chance to test these newly-emerged strategies against other strategies they’ve deemed to be good.

8) Finally, the gamers have the motivation. If you discover a strategy in Starcraft or a deck in Magic the Gathering that truly breaks the game wide open, you have lots of rewards waiting for you. Fame, glory, tournament victories, even fabulous cash and prizes. You’ll have a reputation and in some circles, you’ll finally “be someone.” That’s a lot of incentive for some people. If you’re a tester at a game company and you discover the exact same thing before the game is released, then you get to type up another bug report and get you toys taken away from you. Not quite the same level of incentive.

Female fans of top Magic the Gathering player Ben Rubin await his arrival at a Pro Tour tournament in Sydney, Australia.

Ok, so balancing a game is damned hard. But how to we attempt it? The first step is designing checks and balances into a game from the start. Every unit in Starcraft has a strength and a weakness. Even basic strategies have strengths and weaknesses. Attacking early (at the expense of a strong economy) beats expanding early, but loses to defending early (if the defender can maintain a good economy and survive the attack). Defending early loses to expanding early. Checks and balances. You could even say, paper, rock, and scissors.

Another great example of designing (at least some) balance into a game is Magic the Gathering. There are five colors in Magic, and each one has unique strengths. Blue can counter spells, draw cards, and fly, for example. The more colors you want in a deck, the less consistent the deck will be. If your whole deck is blue, you’ll pretty much always have blue mana whenever you need it (very consistent), but you will also have the built-in weaknesses of blue: you can’t deal with threats once they are in play. You might play blue and white or blue and black to better remove threats (more versatile deck), but now, because of the way mana works in Magic, you are less likely to have the correct colored mana at the right time (less consistent).

Another principle to live by is to try to prevent the situation of a player saying “I knew exactly what the opponent was going to do, but there was absolutely no way to stop it or punish it.” That’s just another way of saying “checks and balances,” really. There are many levels to this concept, though. In a fighting game, you could make sure that whenever someone sits there you can throw them, whenever they attack you can block or parry or do a reversal, and so on. It will feel really scientific as you go through all the different conceptual things a player can do (attack, block, throw, parry, etc.) and make sure each has a counter. But it’s a whole new ballgame when you throw all those options together, in combination. Perhaps a pattern of attack (rather than a single move) is too powerful. That can be difficult to uncover during testing.

That just goes to the next point: get good testers. Game testers are usually paid and treated poorly. That’s really unfortunate. Testers are usually employed to find software bugs, but in competitive games, they really need to be playing the game constantly in order to break it design-wise as well. That’s the only hope of getting anywhere near balanced for launch. I’m a pretty academic guy, but even I would never pretend that someone could take a design document I wrote and turn that into a perfectly balanced game without testing. It’s ALL about testing.

One company acutely aware of this is Wizards of the Coast, makers of the collectible card game Magic the Gathering. This game is played by millions around the world, boasts 80,000 sanctioned tournaments a year(!!!), and routinely gives prizes as high as $50,000. They are serious about making a balanced game. What the game industry would call “testers” they call “developers.” Their developers are pulled from the top ranks of the “Pro Tour” of Magic. Many of them even made a living as Magic players before joining the dev team. They do extensive play testing of every set in a curiously named internal league called the “Future Future League.” Even they aren’t perfect, but they go a long way towards balancing a mind-bogglingly complicated game.

Zvi Mowshowitz wins the Pro Tour Tokyo Magic the Gathering tournament, taking home $30,000. He has lots of incentive to discover and exploit balance problems.

Another company worthy of note is Blizzard. Starcraft is one of the best balanced games ever to be played on the internet, and that’s no accident. Blizzard knows that the release date of a game is not the end; online games require support. Thanks to Blizzard’s expert team of tester and balancers, including lead balancer Rob Pardo, Starcraft was patched several times for bugs as well as balance issues. Blizzard has a wonderful resource in battle.net data to help in balancing. Battle.net is the only legal matchmaking service for the game, so tons of data can be collected about play patterns. They know the percentage of people who play Zerg on the Hunters map, the average win ratio for those players, the average length of a game, and zillion other stats. It’s sure nice to back up anecdotal statements like “Zerg are too good. This one guy can beat me all the time with them” with statements like “Zerg have a 76% win rate in tournament play on Lost Temple.”

Starcraft teaches us another useful balance principle as well: purity of purpose. For the most part, units in Starcraft are designed to each have a specific purpose that doesn’t obsolete any other unit. The more functionally independent each unit is, the better. The reason is that balancing is made that much easier. Consider this example of the lack of purity of purpose. Mutalisks are the fast flying unit of the Zerg. They have a designated size of “small” meaning they take less damage from the “explosive type” damage dealt by most anti-air units. It also means they take less damage from the explosive type damage used by most other air units. Furthermore, mutalisks can attack air-to-air and air-to-ground and they use the same projectile in both situations. This is NOT a good example of purity of purpose. The mutalisk is suddenly a good air-to-air and air-to-ground unit, and what can you do to tone down one but not the other? Chaning the body size to medium would make the unit worse in both situations, as would worsening the shot. If mutalisks are too good (or not good enough) at air-to-ground, you could change the damage dealt by most ground-to-air units. But what about the Protoss photon cannon that uses the same shot for ground an air? If you make that worse to give mutalisks a chance, you just make the Protoss ground defense worse, too, as a side effect. It’s one big mess.

Here's a pack of flying Mutalisks in Starcraft. These suckers were hard to balance, and completely ruled the air in older versions of the game.

In fact, creating functionally independent moves/units/whatever in design is so important, that I’m going to write an article on that, too. There’ll be a link right here when it’s done.

Capcom has a really interesting take on game balance. “Back in the day” they might have tried a more…traditional method of balancing, but these days I’m convinced they have a rather unique way of doing things. Here’s the Capcom Principle of Balance:

Clever, really. They understand balance vs. variety well. They create as much variety as possible, making balancing so impossible, that not only can they not do really do it, but even the huge gaming audience is faced with a task that takes at least a year to sort out.

Capcom will give only this character an instant speed, long-range throw, only this character a ridiculously fast walking speed, only these characters an air-throw. Now hand out the unfair stuff, one or two to each character. Mix it up real good, and bam, now it has so much variety and “imbalance” that in a weird way everything becomes “fair” again. Every character can emphasize their own little unfair thing and considering all the variety thrown in for kicks, there’s bound to be some way to stop said unfair thing somehow. This is the essence of Marvel vs. Capcom 2.

Balance this!
So broken it's almost fair?

Accept that your game will not be balanced without considerable work. Keep your design functionally independent so you can adjust things without stepping on the toes of other things. Hire excellent testers, treat them well, and motivate them to break the game, design-wise as well as bug-wise. Realize that the more variety you include, the more interesting the game will be, but the more difficult balancing it will be. The other route is to go so overboard on features and variety that it will takes years for players to sort out what’s actually broken. If you go that way, be sure to include Capcom in the special thanks section of your end credits.