Designing Puzzle Strike

Puzzle Strike’s gameplay centers around the crash gem system which was inspired by Puzzle Fighter (which I was also lead designer of). The dynamics that result from it are interesting when played at high skill level or a low skill level so that gives the game a solid foundation to appeal to hardcore players and casual players. I’ll explain much more about what goes into pleasing each audience, but first let’s examine the crash gem system.

Crash Gem System

Gem Pile

Each player has a gem pile zone. Your gem pile fills up over time and if you end a turn with too many gems, you lose. Just before you lose, you’re usually at your most powerful though. You can use crash gems to break (remove) your gems and send them to an opponent. The more gems you have, the more ammunition you have. Also, the height bonus rule lets you draw more chips the more gems you have in your gem pile. Drawing more chips gives you a higher chance of drawing crash gems and other combo pieces that let you take more actions on your turn.

You always pass through a period of being very powerful just before you lose. Just before you lose is when you have the most ammo and the biggest height bonus to draw more chips. This specific way of handling the comeback mechanism tends to make games close and intense. This same mechanism worked great in Puzzle Fighter and my goal was to translate that to board game form.

Combine

You can use a Combine chip to join two gems in your gem pile together into a bigger gem. For example, combining two 1-gems gives you a single 2-gem. Combining a 1-gem and a 2-gem gives you a 3-gem. The largest gem you can have is a 4-gem.

Combining makes your crashes stronger. A crash gem only breaks open a single one of your gems. If you use it on a 1-gem, it only reduces your pile height by 1 and only sends 1 gem to your opponent. If you use it on a 4-gem, it reduces your pile height by 4 and it sends 4 1-gems to your opponent. Then your opponent will have to deal with combining those before they can easily crash them back.

Counter-Crashing

Counter-crashing lets you stop an opponent’s crashed gems from reaching you. This lets you control the pace of the game in a strategic way. If no one ever crashed any gems, the game would end after 10 turns. That’s because each player antes a 1-gem at the start of their turn and the game ends whenever a player ends their turn with a pile height of 10 or more. If you crash gems at someone, you might end the game sooner because you’re giving your opponent gems. That said, your opponent might crash gems right back at you later, so on average it still might take about 10 turns to end.

Counter-crashing lets you actually extend the game though because it removes gems from the system. Whenever an opponent crashes gems to you, before those gems reach your gem pile, you have the opportunity to counter-crash. To do that, you use a crash gem to break gems in your own pile and cancel out some of the incoming gems. For example, if 3 gems were coming at you, if you crashed 2 gems of your own, you’d cancel out 2 of the 3 incoming gems. That removed a total of 4 gems from the system (2 in your gem pile, and 2 of the incoming gems). If you counter-crash repeatedly, you’re buying yourself more turns. If your strategy involves getting lots of money and spending it later, or building up a powerful combo and unleashing it later, you need to make sure there is a later. On the other hand, if your strategy is all about rushdown as hard as possible, you want to end the game as soon as possible before other players build up powerful late-game combos.

This diagram shows how rushdown, economy, and defense strategies relate to each other as well as how good each of the 20 characters is at executing that kind of strategy:

Money System

The money system is related to the crash gem system. You use money to buy more chips to add to your deck. Some of those chips give you more money themselves. Having a lot of money chips means you’ll be able to afford other more powerful chips that actually do something, but it’s a common mistake to put too much money in your deck in Puzzle Strike. You need to have Combines, Crash Gems, and various puzzle chips that actually do things.

Crashing and combining gems affects how much money you have. Each time you crash a gem, you get an extra +$1 to spend that turn. (If you crash a larger gem such as 3-gem, you still get only $1.) On the other hand, each time you combine two gems, you get a -$1 modifier on your money that turn. Breaking open gems releases the gem power inside, but it requires energy to fuse two gems together. And if you counter-crash (break open your gems on another player’s turn while they’re crashing at you), you don’t actually get to used that released energy; the $1 bonus disappears before you get reach your next buy phase.

Here’s a short summary of that:

crash a gem: +$1
counter-crash a gem: +$0 (effectively)
combine two gems: -$1

What that means for strategy is that a rushdown strategy has a built-in drawback. If you want to be very aggressive, you’ll very quickly combine your gems into large gems and that will put you behind on money. You’ll then crash your big gems at your opponent(s) and hope to end the game very soon before your lack of money mattered.

The opposite strategy is to counter-crash a lot. That will remove gems from the system and give you more time (more turns) to develop a strong late-game deck. You’re still paying for the right to have more turns though in a way. At least you didn’t lose as much money as those paying for lots of combines, but you also didn’t gain the money you could have by crashing gems on your own turn.

Crashing gems on your own turn while only combining and counter-crashing the minimum amount you can get away with gives you the most money bonus. There are lots of tradeoffs here.

Tournament Level Play

It’s a good sign if a game is of high enough quality that it’s suitable to play at a tournament level. Even if you don’t care about ever attending a tournament for it, it means the game is solid enough to stand up to experts playing it. I find that reassuring because it means you can invest as much time in a game like that as you want and you don’t have to worry about it falling apart or becoming degenerate or boring if you ever get “too good” at it.

Here are the qualities I wanted, to ensure interesting play at high skill levels:

  • Strategically interesting dynamics
  • Player interaction
  • Asymmetric design
  • Getting to the meat of the game quickly
  • Exciting moments built into the system
  • Solid rules

Strategically interesting dynamics

We’ve already covered a lot of this part. The crash gem system and its interaction with the money system create unusual and interesting dynamics. There’s a lot for expert players to explore and a lot of ways they can express themselves in the game system.

Player interaction

A good competitive game needs lots of player interaction—the more the better. Games that are mostly solitaire that you play alongside other people and compare scores are really lacking in drama. They also lack in the primary skill test that you’d hope a competitive game would be about: how you act upon and react against an opponent.

Puzzle Strike’s core mechansim is inherently interactive. Crashing your gems at an opponent affects that opponent and they can counter-crash to interact back with you. Separately from this, there are also “attack” chips (red fist) and “defense” chips (blue shield) that add yet another layer of interacting and reacting to opponents. Puzzle Strike is not a passive-aggressive game of indirect interaction—it’s highly interactive so that there’s more ways to get advantages over your opponents and more ways they can avoid that, too. 

Asymmetric design

Symmetric games are kind of a flat experience after you’ve been exposed to just how rich and varied asymmetric games are. Puzzle Strike has 20 characters, which means there’s 210 different character matchups in just the 1v1 mode of the game. Different matchups play very differently, which is interesting. Different characters allow players to find ones that match their own personality and playstyle. Also, it’s a wonderful property in any asymmetric game that you can learn just one character (or perhaps a small number of characters) and yet still participate in a system far more varied and nuanced than one without different characters to choose from.

Or to put it more bluntly, asymmetric games are just more hype in competitive play. The different characters in Street Fighter, the races in StarCraft, and the decks in Magic: the Gathering have all created tons of hype and excitement that wouldn’t have been possible with a single character, single race, and single deck that everyone plays.

Getting to the meat of the game quickly

This may not sound like an important property, but it really is in competitive play. The game needs to be as efficient as possible because if you have an event where you’re trying to get through many matches with many players (in swiss, or double elimination for example) then you need those matches to be as short as possible or else the tournament becomes too long to comfortably run. Every turn in the game should pull its weight. Even if you never play in a tournament, you should appreciate this anyway. Removing filler turns gets you to the fun that much faster.

Some deckbuilding games start you with what are basically blank cards in your deck, usually victory point cards that get added up at the end of the game. Puzzle Strike replaces those blank cards with your character chips. So your most interesting actions are there from the start, and you can actually start doing stuff on turn 1 and 2.

Exciting Moments Built Into the System

Any game that can hold up to competitive play is probably capable of generating exciting moments. That said, we can certainly influence how often these moments happen by adjusting the game design. Puzzle Strike is specifically tuned to intentionally create exciting moments often.

A lot of this is from the crash gem system, as described above. Players are inherently more powerful as they are about to lose, so close games are frequent. Another thing that makes exciting moments even more frequent is the way the game checks the lose condition. If you end your turn with a pile height of 10 or more, you lose, but you CAN have more than that during your turn. An opponent might send a lot of gems to you and you might start your turn with a total of 15 or more. Dire straits! But over the course of your turn, you might be able to do a huge combo that digs yourself down to 9 or fewer gems. The height bonus lets you draw the maximum number of chips in this case, so you’re actually more likely to pull off a spectacular turn that barely saves you.

Solid rules

This could be a whole article in itself, but basically game rules need to be very solid to allow experts to play as hard as they can. You can’t have rules that involve judgment calls of some third party. You can’t have rules that say you can’t make a certain kind of move “too much.” You can't require shuffling of cards that have different card backs. You can’t have rules about communication with other players that say “you can talk, but you can’t share certain types of information.” You can't have legal moves that make the game degenerate to play and then say it's "not in the spirit in of the game" to use those moves. There’s a whole lot of sloppy things you can’t do. Puzzle Strike is designed with serious play in mind, and has rules suitable for players who are trying their hardest to win.

Casual Play

For a game to have casual appeal, it actually needs some of the same things we just mentioned. Most importantly, it still needs interesting dynamics, it’s just that those must be apparent right away, even if you’re bad at the game. All the things that make Puzzle Strike interesting to experts still count here because even beginners can see how the crash gem system works.

Another element of casual play is being able to involve more players. Puzzle Strike has a 2v2 mode and a 3p and 4p free-for-all mode. The free-for-all mode is very interesting and I’d go so far as to say that it’s my contribution to the field of how to make free-for-all modes.

Free-for-All

A common problem with free-for-all modes is that they are too dominated by pre-game alliances. That means if you and a friend play with two other strangers, your ability to team up (even if it’s kind of unconsciously) with your friend can be too overwhelming. If a game is decided before you even start just because you have a friend in it, that’s poor design even for casual play.

Another common problem with free-for-all modes is that doing nothing is the best strategy. Let other players fight each other and weaken themselves, while you grow stronger. That’s really boring, yet it’s almost the default way that most free-for-all games work.

Finally, kingmaker and lame duck are common (and bad) qualities in free-for-all games. Kingmaker is when a player who can’t possibly win gets to decide who does win. Lame duck is when a player who can’t possibly win is technically still playing. This feels stupid and pointless to the lame duck player, and allowing this situation to happen at all greatly increases the chance of kingmaker situations.

Puzzle Strike’s free-for-all mode avoids and minimizes ALL of those problems. It works in a fairly unusual way. You are able to crash gems at any opponent you want, but you can’t actually gang up to eliminate someone that way. That’s because there’s no player elimination; instead, the game ends the moment that anyone ends their turn with a full gem pile. The player with the least gems in their gem pile wins.

Whenever someone is about to lose in this free-for-all mode, someone else is about to win. And anyone else playing has incentive to help the would-be loser to prevent the game from suddenly ending. They can do that by counter-crashing for that victim to help them out. To put it another way, whenever you’re about to lose, you always have at least one friend in the game whose incentive it is to help you. Who that friend is depends on the pile heights and what’s happening in the game, not on who you’re real life friends with outside of the game.

Furthermore, there isn’t really lame duck. If you’re still playing, you can still win. And the lack of lame duck means that kingmaker is minimized. There’s even a special rule to minimize it more: if you have a ton of gems in your gem pile and you’ll surely lose, you can’t just crash some in such a way as to decide the winner. Your crashed gems remain “floating” until you prove that you can dig yourself out below 10.

Components

I talked a lot about game dynamics that are fun in a casual setting, but there’s also a tactile and visual element to it all that’s really important.

Boards

The boards in Puzzle Strike help you organize your gem pile and other zones, and have some helpful reminder text. They also look like a video game (like Puzzle Fighter sort of) and that gets you in the spirit of things.

Screens

The screens (or “shields”) let you hide your chips from other players if you’re having trouble holding them in your hand. They’re pastel colored and they each depict a different game rule in Puzzle Strike in a fun way using 8-bit versions of the characters.

Chips

Most deckbuilding games are playing with cards. These types of games require a lot of shuffling though, and the form factor of chips allows you to draw them from a bag without having to worry so much about frequently shuffling cards. Players who are bad at shuffling, and even players who are good at shuffling have often said the unusual form factor is kind of charming.

The Box

It’s kind of bold to have a pink box! The cute characters and distinctive pink box have gotten a lot of people to try the game who would have been intimidated by a more serious looking box. Silly as that sounds, the packaging matters!

Conclusion

The crash gem system that’s the core of Puzzle Strike captures some of the best qualities of the Puzzle Fighter. It’s strategically interesting to experts, yet still accessible to beginners. Puzzle Strike is designed to be a solid tournament game, yet didn’t really have to sacrifice much of anything to have plenty of casual appeal too.

You can get the tabletop version here or play it online here.

Balancing Multiplayer Games, Part 1: Definitions

Balancing a competitive multiplayer game is difficult—really, really difficult. In this article I’ll define the terms that will help us discuss the topic, then in the second and third articles I’ll explain what counts as balance and some techniques to work toward it. Then in the fourth article, I’ll try to impress upon you what deep trouble we’re really in. It's a wicked problem that by its very nature is resistant to complete mathematical analysis. We'll have to do it different way.

First, the terms. Let’s start with balance and depth as defined by my former selves:

A multiplayer game is balanced if a reasonably large number of options available to the player are viable--especially, but not limited to, during high-level play by expert players.
—Sirlin, December 2001

 

A multiplayer game is deep if it is still strategically interesting to play after expert players have studied and practiced it for years, decades, or centuries.
—Sirlin, January 2002

 

 

This definition of balance is pretty good, but there are two concepts hiding inside that term viable options. On one hand, I meant that the game doesn’t degenerate down to just one tactic, and on the other hand, I meant that if there are lots of characters to choose from in a fighting game or races to choose from in a real-time strategy game, many of those characters/races are reasonable to pick. Let’s call the first idea viable options and second idea fairness in starting options, or just fairness for short.

Viable Options: Lots of meaningful choices presented to the player. They should be presented with enough context to allows the player to use strategy to make those choices.

Fairness: Players of equal skill have a roughly equal chance at winning even though they might start the game with different sets of options / moves / characters / resources / etc.

Viable Options

The requirement that we present many viable options to the player during gameplay is what Sid Meier meant when he said that a game is a series of interesting decisions (a multiplayer competitive game, at least).

If an expert player can consistently beat other experts by just doing one move or one tactic, we have to call that game imbalanced because there aren’t enough viable options. Such a game might have thousands of options, but we only care about the meaningful ones. If those thousands of options all accomplish the same thing, or nothing, or all lose to the dominant move mentioned above, then they are not meaningful options. They just get in the way and add the worst kind of complexity to the game: complexity that makes the game harder to learn yet no more interesting to play.

For the sake of depth, we also hope that the player has some basis to choose amongst these meaningful options. If the game at hand is a single round of rock, paper, scissors against a single opponent, there is nearly no basis to choose one option over the other so it’s hard to apply any kind of strategy. And yet a game of Street Fighter might be decided by a single moment when you choose to either block, throw, or Dragon Punch, or a game of Magic: the Gathering might be decided by a single Master of Predicaments decision. These examples at first glance look like the rock, paper, scissors example, but the decisions take place inside the context of a match that has many nuances where each player is dripping with cues about their future behavior. In Street Fighter and Magic, the player does have basis to choose one option over the other, and more than one choice is viable, we hope.

 
 
 

Also for depth, we prefer if the meaningful choices depend on the opponent’s actions. Imagine a modified game of StarCraft where no players are allowed to attack each other. All they can do is build their base for 5 minutes, then we calculate a score based on what they built. There are many decisions to make in this game, and it might have several paths to victory, but because these decisions are purely about optimization—more like solving a puzzle than playing a game—they make for a shallow competitive game. Fortunately, in the actual game of StarCraft, you do need to consider what your opponent is building when you decide what to build.

While we require many viable options to call a game balanced, the requirement about giving the player a context to make those decisions strategically and the requirement that the decisions have something to do with the opponent’s actions are really about depth. They’re worth pointing out though because we should attempt to increase the depth of the game as we balance it, not decrease it.

Fairness

Fairness, in the context I’m using it here, refers to each player having an equal chance of winning even though they might start the game with different options. In Street Fighter, each character has different moves, in StarCraft each race has different units, and in World of Warcraft, each arena team has different classes, talent builds, and gear. Somehow, all of these very different sets of options must be fair against each other.

I want to stress that I am only talking about options that you’re locked into as the game starts. That’s a very important distinction. Options that open up after a game starts do not necessarily have to be fair against each other at all. Imagine a first-person shooter with 8 weapons that spawn in various locations around the map. Two of these weapons are the best overall, 3 are ok but not as good as the best weapons, and the remaining 3 are generally terrible but happen to be extremely powerful against one or the other of the 2 best weapons.

Is this theoretical game balanced? It certainly might be, meaning that nothing said so far would disqualify it. A designer could decide that they want all weapons to be of equal power, but they need not decide that as long as each weapon is still a viable choice in the right situation. It might be fine to have two powerful weapons that players compete over, a few medium power weapons that are still ok, and some weak weapons that allow players to specifically counter the strong weapons. There could be a lot of strategy in deciding which parts of the map to try to control (in order to access specific weapons) and when to switch weapons depending on what your opponents are doing.

By contrast, a fighting game with 8 characters designed by that scheme is not balanced because it fails the fairness test. Players choose fighting game characters before the game starts, but they pick up weapons in the first-person shooter example during gameplay. Being locked into a character that has a huge disadvantage against the opponent’s character is unfair.

Games that let players start with different sets of options are inherently harder to balance because they must make those sets of options fair against each other in addition to offering the players many viable options during gameplay.

Symmetric vs. Asymmetric Games

Let us call symmetric games the types of games where all players start with the same sets of options. We’ll call asymmetric games the types of games where players start the game with different sets of options. Think of these terms as a spectrum, rather than merely two buckets.

 

Symmetric                          Asymmetric
<---------------------------------------------->
Same starting options                            Diverse Starting options

 

On the left side of the spectrum, we have games like Chess. In Chess, each side starts with exactly the same 16 pieces. The only difference between the two sides is that white moves first. Because of this different starting condition, we shouldn’t say that Chess is 100% symmetric, but it’s damn close. If Chess were the only game you had ever seen, you might think that the black and white sides are played radically differently; white sets the tempo while black reacts. There are entire books written about how to play just the black side. And yet if we zoom out to look at the many games in the world, we see that the two sides of Chess are so similar as to be virtually indistinguishable when compared to two races in Starcraft, two characters in Street Fighter, two decks in Magic: The Gathering, or two armies in Chess 2.

 
 

The more diversity in starting conditions the game allows, the farther to the right of our spectrum it belongs. So asymmetry, as we mean it here, is a measure of a game’s diversity in starting conditions. This is not meant to be an exact science, so there is no specific formula to determine where a game belongs on this spectrum, but it’s a handy concept anyway.

Let’s look at a few examples. StarCraft has three very diverse races so it belongs toward the right side of our spectrum. That said, even if the three races were as different as imaginable from each other, the number three is small enough that we shouldn’t put it at the far right (admittedly, this is a judgment call). Fighting games can have dozens of characters that play completely differently and they tend to have more asymmetry than most other types of competitive multiplayer games.

That said, individual fighting games can vary quite a bit in just how asymmetric they are. Virtua Fighter, for example, is an excellent and deep fighting game, but the diversity of characters is relatively low compared to other fighting games. All characters have a similar template compared to Street Fighter where some characters have projectiles, or arms that reach across the entire screen, or the ability to fly around the playfield. Meanwhile, Guilty Gear, a fighting game you might not have have heard of, has more diversity than any other game in the genre that I know of. One character can create complex formations of pool balls that he bounces against each other, another controls two characters at once, another has a limited number of coins (projectiles) that power up one of his other moves and a strange floating mist that can make that powered up move unblockable. It’s almost as if each character came from a different game entirely, yet somehow they can compete fairly against each other. Guilty Gear is possibly all the way to the right of our chart because it has both wildly different starting options (characters) and many of them (over 20!).

Magic: The Gathering is also extremely asymmetric in the format called constructed where players bring pre-made decks to a tournament. The variety of possible decks is staggering and tournaments usually have several different decks of roughly equal power level, even though they play radically differently.

First-person shooters tend to be very far toward the symmetric side of the spectrum, usually offering the same options to everyone at the start, except for spawning location. Remember that picking up different weapons during gameplay, or even changing classes during gameplay in Team Fortress 2, does not count as asymmetric for our purposes. (Again, because those different options don’t need to be exactly fair against each other.) Also, first-person shooters that do have asymmetric goals for each side often make the sides switch and play another round with roles reversed so that the overall match is symmetric.

Now that we’ve mapped out where some games fit on our spectrum, remember that this is not a measure of game quality. If your favorite games appear on the left (symmetric) side, that does not mean they are bad. If you like StarCraft more than Guilty Gear, you do not need to be upset that Guilty Gear is “more asymmetric.” The spectrum is simply meant to give us an idea about how different the starting options of a game are, not about the depth or fun of the game. That said, I do personally prefer asymmetric games and they are inherently more interesting to me.

No matter where a game appears on this spectrum, it still needs offer many viable options during gameplay to be balanced. In addition to this, the farther a game is to the right of the spectrum, the more it needs to care about balancing the fairness of the different starting options. In the next part of this series, I’ll talk about how we can design games that make sure to offer enough viable options and in the article after that, I’ll explain how we can attempt to create fairness in those pesky asymmetric games.

Balancing Multiplayer Games, Part 2: Viable Options

In the previous article I divided the idea of balance into the two sub-concepts of viable options and fairness. I also defined the concepts of symmetric and asymmetric games, where the more varied the different starting options are that must be fair against each other, the more asymmetric the game is.

How do we make sure we have enough viable options during gameplay?

Yomi Layer 3

The worst thing you can have in a competitive multiplayer game is a dominant move (or weapon, character, unit, whatever). I don’t mean a move that is merely good, I mean a move that is strictly better than any other you could do, so its very existence reduces the strategy of the game. A dominant move also probably has no real counter, so even if the opponent knows you will do it, there’s not a lot they can do.

To protect against dominant moves, we should be aware of the concept of Yomi Layer 3. I wrote a chapter in my book about it, but I’ll quickly summarize it here. “Yomi” is the Japanese word for “reading,” as in reading the mind of the opponent (and it’s also the name of my strategy card game). If you have a powerful move and use it against an unskilled opponent, I call that Yomi Layer 0, meaning neither player is even bothering with trying to know what the opponent will do. At Layer 1, your opponent does the counter to your move because they expect it. At Layer 2, you do the counter to their counter. At Layer 3, they do the counter to that.

Let's look at an example of a Yomi Layer 3 situation in Street Fighter HD Remix. Honda wants to do his torpedo move get close to Ken, but Ken throws fireballs to prevent this.

I gave Honda the ability to destroy these fireballs with his torpedo, but only with the jab version of the move that doesn’t travel very far. If Honda can destroy a fireball with it and end up closer, that’s good for him. Another similar option is that Honda can do his flying buttslam move to avoid Ken's fireball and land on him.

Ken can counter either of those by not throwing the fireball in the first place and letting Honda do the jab torpedo or buttslam. As Honda is moving forward with his jab torpedo, Ken can walk forward and sweep, hitting the recovery of the jab torpedo. Against a buttslam, Ken might walk backward a little bit, then sweep to hit the recovery.

I did not need to add anything to allow for Yomi Layer 4 though because Honda can counter Ken’s wait-and-sweep options by simply doing the original, full-screen torpedo. Yomi Layer 4 tends to wrap around like this in competitive games.

Summary of the options:

Honda: torpedo that goes far -OR- jab torpedo that destroys fireballs / buttslam
Ken: fireball -OR- wait and sweep

This type of thing is very common in just about any competitive game. To put it more generally, you and your opponent each have two options:

You: A good move and a 2nd level counter
Opponent: A counter to your good move and a counter to your counter

The designer generally does NOT need to design Yomi Layer 4 because at that point, you can go back to doing your original good move. 

The Yomi Layer concept is a reminder that moves need to have counters. If you know what the opponent will do, you should generally have some way of dealing with that. As you go through development of a game, ask yourself if various gameplay situations you find yourself in support Yomi Layer 3 thinking. If they don’t there might be a dominant move in there somewhere, which is bad.

Local vs. Global Balance

Does every possible situation in a game need to support Yomi Layer 3?
Answer: no.

Does every possible situation in a game even need to be fair to both players?
Answer: definitely not.

Remember that I defined fairness by the overall chance of winning, given different starting options. Think of that as a global term, in that it applies to the game as a whole from the start of gameplay until someone wins. But the local level, meaning a particular situation in the middle of gameplay, does NOT need to be fair. Even symmetric games like Chess are supposed to have unfair situations. When you have 3 pieces left and the other guy has 9 pieces left, it’s supposed to be unfair to you. Or in StarCraft, if we find that two Zealots beat (or lose to) 8 Zerglings—even though they cost the same resources to make--that is perfectly fine. We don’t care if local situations like that are unfair or not, we only care if Protoss is fair against Zerg.

Checkmate Situations

I call a situation a checkmate situation if it means that one player has almost certainly won, even though the game isn’t actually over. For example in Super Street Fighter 2 Turbo, if Honda lands his deadly Ochio Throw against Guile in the corner, he can then follow up with a series of moves (involving more Ochio Throws) that virtually guarantee victory. Human error could change the outcome, but as soon as you see that first move, you know it should be a checkmate.

Are checkmate situations ok? They clearly violate our requirement that there be many viable moves (Honda really only has one option here and Guile has no good options). They clearly violate the concept of Yomi Layer 3. And yet, the answer is that checkmate situations can be ok. It’s sooooo hard for Honda to get close to Guile in this match, that if he does, he basically deserves to do 100% damage. All the gameplay that takes place before the checkmate is pretty good, and even though Honda can do this abusive thing up close, the match is still heavily in Guile’s favor overall.

I’d like to point out the other side of this argument though. Some players think that even though Guile has the advantage in this match, Honda’s ability to repeat that Ochio Throw is too degenerate. They say yes he needs it to win, but the game would be better overall if things weren’t so extreme. If only Honda could get close to Guile a little more easily, then he would not need a checkmate situation.

I think Rob Pardo, VP of Game Design at Blizzard, echoed this sentiment in a lecture he gave at the Game Developer’s Conference on multiplayer balance. He said that “super weapons” in real-time strategy games are generally a bad idea. They leave the victim feeling that there is nothing they could have done (checkmate!). He explained that even though the Terran nuclear missile in StarCraft looks like a super weapon, it has many built-in weaknesses: a ghost unit must be nearby the victim’s base, there is a red targeting dot on the victim’s base, and a 10 second countdown is announced to the victim, giving him time to destroy the ghost to prevent the nuclear missile.

Pardo has a good point and so did the players who complained about Honda. Even though I think checkmate situations can be ok, it’s telling that when it was my turn to make the decisions, I removed Honda’s checkmate situation in Street Fighter HD Remix. In that game, I gave him an easier time getting close to Guile, but replaced his checkmate situation with a Yomi Layer 3 situation so there’d be more viable decisions throughout the match.

Lame-duck Situations

Lame-duck situations are just like checkmate situations, but with one difference: time. Honda’s checkmate situation takes something like three seconds to get through. But consider a similar situation in the fighting game Marvel vs. Capcom 2. In that game, each player has a team of three characters: one on the playfield and two on the bench. Players can call in one of their benched characters for an assist move at any moment, letting them attack in parallel with their main character and assist character at the same time. Or better yet, they can stagger the attacks so that each attack covers the recovery period of the other.

When one player is down to their last character, they can no longer call assists. Fighting with just one character against an opponent with two or three characters might as well be checkmate, almost all the time. The problem is that it takes excruciatingly long for the match to actually end. It takes so long, that I call that last portion of the game the lame-duck portion. Other fighting games are exciting right up to the last moment, but a lame-duck portion of gameplay means the real climax is somewhere in the middle, and then players are forced to act out a mostly pointless endgame while spectators lose interest. Yes, on rare occasions someone pulls off an amazing comeback, comebacks also happen in games without lame-duck endings, so that’s not a good argument.

The lame-duck situation was specifically addressed in Marvel vs. Capcom 3 by adding the X-Factor mechanic. That's a mode you can activate once per game that powers you up a huge amount for several seconds. It powers you up more the fewer characters you have left. Activating X-Factor when you're down to your last character is so powerful that you can reasonably hope to defeat one or two of the opponent's characters before your X-Factor runs out.

While a checkmate situation is maybe ok, you should try to avoid game designs that allow for long lame-duck endings. Both Chess and StarCraft have this undesirable property, and it just means that players often concede the game before the actual end. Those games also show that it’s not the worst thing in the world to have lame-duck endings (because Chess and StarCraft are still good games), but you should still avoid them as a designer if at all possible.

Chess 2 avoids almost all those lame duck situations with the inclusion of the midline invasion rule. That rule is an alternate win condition: if you cross the midline of the board with your king, you win. If you are really so far behind that you can't reasonably come back by checkmate, then the opponent will probably have already won by midline invasion. Furthermore, it's easier to make a comeback when that rule exists than if it didn't, so we both eliminated lame-duck situations and allowed for more exciting comebacks with a single new rule.

Explore the Design Space

Design space is the set of all possible design decisions you could possibly make in your game. Whether your game is symmetric or asymmetric, it’s usually a good idea for your game to touch as many corners of the design space as possible. This helps give a game depth and nuance, but also tends to protect you from dominant moves.

For example, in the virtual card game I designed called Kongai, each character has four moves. When a move hits, it has a percentage chance to trigger an effect. For a given character, we could vary the damage, speed, and energy cost to come up with four different moves. If that’s all we did, though, we’d be missing out on a chance for more diversity in the game, and we’d get dangerously close to making some of those moves strictly better than others which would reduce the number of viable options. Instead, I tried to explore the design space as much as possible with different effects. One move can change the range of the fight from close to far, which is usually only possible before the attack phase. Another move deals enough damage to kill every character in the game, but only four turns after you hit with it. Another move can hit characters who switch out of combat, even though switching out usually beats all attacks.

The point is that by exploring the design space as much as possible, it’s a lot harder for players to judge the relative value of moves. How good is a 90% chance to change ranges during combat as opposed to a 95% chance to hit a switching opponent with a weak move? It’s hard to say and depends on a lot of factors, and that’s good because it means each move is likely to be useful in some situation and knowing when is an interesting skill to test. Incidentally, I call that skill valuation.

Players want you to explore the design space, too. When everything is too similar in a game, it feels like one-note design rather than a symphony. The more nuances and different choices you present, the more each player can express his own playstyle.

Wheat from the Chaff

Here’s my favorite quote from Strunk & White’s The Elements of Style:

Omit Needless Words
Vigorous writing is concise. A sentence should contain no unnecessary words, a paragraph no unnecessary sentences, for the same reason that a drawing should have no unnecessary lines and a machine no unnecessary parts. This requires not that the writer make all his sentences short, or that he avoid all detail and treat his subjects only in outline, but that every word tell.


Treat your game design the same way. Yes you should explore the design space, but omit needless words, mechanics, characters, and choices. Although your primary goal regarding viable options is to make sure you’re giving the player enough options, your secondary goal should be to eliminate all the useless ones.

Marvel vs. Capcom 2 has 54 characters, which is ridiculously many. How many are viable in a tournament? I’ll say 10, and I’m being generous. I actually call that a success because coming up with 10 characters in fighting game that are fair against each other is really hard. That said, it does look pretty bad to have more than FOUR TIMES that many characters sitting around in the garbage pile of non-viable choices. Compare this to Super Street Fighter 2 Turbo’s 16 characters, almost all of which are tournament viable; or Guilty Gear’s 23 characters, almost all of which are viable; or Yomi's 20 characters, all of which are tournament viable, and you see what a compact design looks like.

One genre of game is notable for intentionally creating an enormous number of useless options: collectable card games. Even though Magic: The Gathering has many good design concepts and several viable decks at any given time, when we judge it on how much chaff it has—cards/decks that aren't viable in the tournament environment—it's one of the worst situations of just about any game.

MTG’s Mark Rosewater defends the intentional inclusion of bad cards for design reasons, but really it's entirely marketing driven. Their business is to put a collectable barrier between you and the the cards you want so as to sell more packs of those cards. That means mountains of chaff cards are inventible. I think even one single chaff card is a problem that would ideally be fixed, but Rosewater claims that bad cards are ok because they:

a) allow for interesting experimental mechanics that might end up being bad
b) test valuation skills because if all cards were equally good, there’d be less strategy
c) give new players the joy of discovering that certain cards are bad, as a stepping stone to learning the game
d) are necessary because even if they came out with a set that consisted entirely of known good cards from old sets, there’d still be only 8 tournament viable decks and the rest of the cards would not be used.

The solution to this problem is clear if we only cared about design and not rip-off marketing: print fewer cards. Reason a) is a great one, experimental cards that end up accidentally bad are fine. Reasons b) and c) are just silly. Saying the game would not have enough strategy if bad cards were removed is an insult to Mark’s own game. Saying that new players need to discover the intentionally bad cards is even more silly because this comes at the cost of making sets overwhelming to new players and needlessly unwieldy for expert players. We all know the real reasoning here is to make players buy more random packs of cards to get at the few good ones.

Finally, reason d) is a blatant admission that the game should have fewer cards. Ironically, I’m not even sure d) is true. Maybe printing a large set of all good cards really would lead to more viable tournament decks than the game currently supports. If not though, they should stop printing all that chaff. Here's an example of a card that doesn't need to printed:

You could say that MTG proves that it’s really all about chaff, though. Giving a few viable options amidst a sea of bad ones is probably good business when you sell by the pack. But we don’t see this in other genres and really we just haven’t seen anyone crazy enough to stand up to MTG on this issue and offer a competing card game that’s just as well designed but that eliminates all chaff. (Disclosure: Codex is that game and is in development now.)

League of Legends is also notable for its chaff, though to a lesser extent than Magic: the Gathering. When you sell by the character, it's hard not to make more and more characters forever—way more than would make sense to try to balance. Such a game might only need 30 characters to cover all necessary archetypes and it could then be balanced really well. When you go past 100 in such a game, you then need a bandaid system of character bans at the top end and you're practically guaranteed to have a bunch of chaff characters at the bottom end. But it sure would make more money to sell 100 characters rather than 30.

Lots of chaff and/or having to ban characters routinely is pretty ugly design.

Double-blind Guessing

I used the technique of double-blind guessing in both my Yomi card game and my Kongai virtual card game (that one’s actually a turn-based strategy game dressed up like a card game). Anyway, the idea is to make all players commit to a choice before they know what the others have committed to. This is the same setup as the prisoner’s dilemma.

I learned this concept from fighting games. Though they appear to be games of complete information because you can see everything the opponent can see, fighting games are actually double-blind games. They come down to very precise timing and the moment you jump, you often don’t know that the other guy threw a fireball. You only know that 0.3 or 0.5 seconds ago he didn’t. It takes a small amount of time for the opponent’s move to register in your brian, and though it might seem insignificant, it’s actually critical to fighting games even working as strategy games at all.

Real-time strategy games like StarCraft have the same property, but on a much slower time-scale. You often do not know exactly what the opponent is building in his base at the moment you must decide what you should build. Even if you were able to scout his base, you might be working on information that’s several seconds old, so you have to guess what he did during that time.

If we were to remove the double-blind nature from my two card games Yomi and Kongai, and from fighting games and real-time strategy games, I think all of them would be broken. All those games need double-blind decision-making to be interesting. This design pattern is a way to increase the chances that you have many viable moves in your game because it naturally forces players into the Yomi Layer 3 concept I talked about earlier. Weaker moves become inherently better in a double-blind game because it’s easier to get away with doing them without being countered. I’ve even joked that some matches between the world’s best Virtua Fighter players are “a battle of the third-best moves.” Sometimes the players are so paranoid about doing their “best” option for fear of being countered, they fall back on a third best option that no one would ever counter (though it’s quite a sight when the opponent counters even that!). If no guessing was involved at all, players would not use third-best moves.

Playtesting

Finally, playtesting, especially with experts, is how you figure out where your problems really are. Do the experts ignore some vast portion of you game’s moves? Have they discovered a bunch of checkmate situations that you didn’t know about? Do you see them using a variety of strategies?

How to use playtests is really a whole topic of its own, but here’s a few points to keep in mind. First, be skeptical of them. Gamers tend to overreact to changes and claim that no counters exist to some strategies when counters do, in fact, exist. It can take years to sort out what is really effective in a game, and playtesters during your beta are only on the first few steps of that long journey. If they find what looks like the best strategy in the game, it might just be that they have found a local-maximum. Maybe some radically different way of playing that they have not yet discovered ends up being more powerful. This is actually par for the course in fighting games and it hasn't been much different in my work on tabletop games, either.

That said, playtests are really all you have. Theory is not a substitute for experts playing against each other and trying their hardest to win. I think everyone knows they need playtests, but the hardest question is who do you listen to when all your playtesters disagree, and how do you know when playtesters are wrong about how powerful something is? That question is so hard that I’ll save it for part 4 of this series when I tell you how much trouble we’re really in trying to balance a game at all.

Conclusion

To ensure we have many viable options, building in counters with the Yomi Layer 3 system is a good start. Not all situations need this though, and checkmate situations might be acceptable, but you should avoid their their longer cousins, lame-duck situations, if possible. Explore your game’s design space by offering moves as different as possible because this technique has a good chance of making all moves useful somewhere and it makes it very difficult to determine what the best moves really are. That becomes an interesting skill test for players. Eliminate all the worthless options because they confuse the player and add nothing, but they make you a lot of money in a certain genre. The double-blind guessing mechanic helps keep more moves viable than otherwise would be.

And finally, all the theory in the world does not substitute for playtesting.