GDC 2010: Design in Detail XVI


Sometimes you have to let your head drive.

I’ve claimed in this talk that your rational brain is a feeble instrument and cannot handle the volume of input associated with balancing a multiplayer game. This is true, but that is not an excuse for presenting your design decisions as inexplicable black magic guided solely by intuition and guesswork. You need to have solid design values that you can point to as a general explanation for how you make decisions, and then provide specific reasons and supporting data when necessary to convince the team. Just because you don’t have time to carefully examine every detail doesn’t mean you can’t logically examine any decision. Other designers and developers have instincts, too; if they clash with yours take it as a sign that you need to look closer.


Here are some good design values to use when balancing a complicated game system. First, fix imbalance with physics when you can, and only revert to math when required. The player cannot directly experience the math behind the system, so tweaking elements by changing mathematical formulas is difficult to perceive, tough to evaluate and even if it does fix the problem in the long-term, it may not feel fixed. Of course, at their most basic level all video games software are math, so it may be impossible to address a problem without making changes to numbers and equations, but don’t resort to that immediately. I think a lot of designers got their start with board games and pen-and-paper RPGs, where the math is explicit, but modern games are simulations and respond more readily to behavioral changes than to statistical ones.


Hey look, a totally fair game… A totally boring, pointless, frustrating, fair game.


You cannot make a Sniper Rifle fair. The person being sniped cannot counter-attack, faces near-instant death, and usually doesn’t even know they are in a fight until it is too late! If you make fairness your goal you will end up removing all the interesting asymmetry from the game. Instead, focus on longevity. Create a Sniper Rifle that doesn’t make the person that was sniped want to quit, and you will succeed.

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Balance of Power II

Tank Beats Everything

Even in the case where an element cannot be limited by role, it can be limited by availability.  Sometimes the Player should feel overpowered, either as a reward for a good player or as a temporary boost for an average player.  A game that is nothing but a relentless competence test can become monotonous, especially once a player has reached the limits of their physical ability to get better.  Giving them an occassional taste of unmitigated power relieves the pressure to perform and is an excellent palate cleanser.  An element that is fun and fulfills a player aspiration but can’t be limited to a single role is an excellent candidate for this experience.

No mana?  No problem!

Take that, Rock, Paper and Scissors

A successful transition from “balanced” to “overpowered” usually requires some changes, though.  It needs to be exaggerated so the sounds, effects, even the fiction, match the new power level.  It should become a featured element on a single level or two, the player should feel special for getting to use it, and the enemy resistance should be ratched up as well to highlight how strong they have become.  The element should also be made as modal as possible, so the player knows when the “overpowered” experience begins and it is clear when it is supposed to end and resume normal gameplay.

In a Corner

Let’s say an overpowered element doesn’t fit in any of these categories.  It isn’t just a perceived imbalance, the other elements can’t be strengthened to an equivalent power level, the role can’t be limited or enforced, and it isn’t appropriate for an over-the-top set piece.  If nothing else can be done, it has to be weakened somehow, right?  Let me tell you about The Needler

The Needler is a weapon from the Halo series.  It fires a stream of neon pink projectiles that actively track enemy targets.  On impact, each needle embeds itself into armor or flesh, remaining there for a few seconds before detonating and causing further damage.  If a character ever has more than 5-6 needles attached at any given time, they all explode in a particularly lethal chain-reaction known as the “Pink Mist”.  It first appeared in Halo 1 and was the bane of my existence for 10+ years because it was incredibly fun to use, but equally impossible to balance.

Like this, only a couple feet lower

I feel a headache coming on

It would start out too powerful, so we would weaken it.  Which would make it useless, so we would change the mechanics.  Which would make it effective in too many situations, so we would limit its placement.  We ended up drastically weakening it right before we shipped to prevent it from wrecking the game.  Three times!  The amount of effort, thought, debate, programming and art resources, playtesting surveys, data analysis and sleepless nights that were poured into the Needler far outpace any four other weapons combined.

So, even if an element cannot be balanced in any other way, the answer is still not to weaken it, but to cut it completely.  It is too difficult to weaken an element without destroying what made it fun in the first place, and the end results won’t be worth the hassle.  It’s best to just save it for another game where it will fit without compromise.

Balance of Power

“Iron sharpens iron, and one man sharpens another”

-Proverbs 27:17  [ESV]

“The whats-it is too powerful.”  It could be a weapon, an RTS unit, a character in a fighting game, a multiplayer class… it doesn’t matter because all chronic balance problems follow the same general pattern.  The game starts to revolve around a single dominant element, which is inherently overpowered and reduces the game’s strategic complexity, ultimately limiting its longevity.  Nobody notices when a single element is too weak, because they just avoid it.  And nobody complains when a dominant element increases strategic complexity, because that makes the game better and more fun.  And a simple problem, like a damage value that is just set too high, usually has a simple solution that is quickly applied.  But for chronic, fundamental balance problems, the designer is repeatedly faced with the same decision.  Should the dominant element be weakened for the sake of balance?  (Hint:  The correct answer is always “NO!”)

Perception is Reality

First, it is important to recognize that the only “balance” that matters is the balance that players perceive.  The goal of balance is longevity, and if players continue to play because they believe the game is fair, it doesn’t matter if it is objectively balanced in some measurable sense.  In fact, if a large enough community perceives the game to be balanced, but your metrics claim it isn’t, then the metrics are wrong.

Nice Gear

Sometimes power is deceptive

So often the problem isn’t that an element is too powerful, but that it feels too powerful.  Maybe its a gun with a really great firing sound.  Or a new unit that players haven’t figured out how to counter yet.  Or perhaps it appeals more to skilled players or everyone is using it because it is new and novel.  These problems usually fix themselves if they are left alone.  I changed the perception of an “overpowered” weapon during Halo’s development just by announcing that I had fixed it (even though I hadn’t actually changed anything.)

The Tooth Fairy is Overpowered

In almost every case, there is no such thing as an “overpowered” element; there are well-tuned elements in a crowd of underpowered, ill-tuned alternatives.  The Sniper class is implemented and all of the sudden you can’t take three steps without being headshot from across the map.  The problem is not that the Sniper is strong, but that the Medic and the Engineer are weak.  It’s easier to make a potent Sniper, so it immediately outclasses the rest.  Instead of spending time figuring out how to cripple the Sniper, focus on making the other classes equally awesome.  Or better yet, ditch the ones that will never feel as powerful as the Sniper and choose different classes that have their own natural strengths.

Get it?  Because neither one exists!

His only weakness is his terrible agent

 

Too Powerful, or All-Powerful?

In the paper design balance pass, every element should have been given a role to fill.  Sometimes an element breaks the balance by breaking its designated role.  An anti-vehicle missile that can be used against a crowd of infantry.  A “glass cannon” that can hold his own in a melee fight.  A long-distance weapon that is just as effective at point-blank range.  The solution in this case is not to weaken the element, but to restrict it so that its strength cannot be applied in as many situations.

Often it takes ingenuity to limit a weapon without weakening it, but it isn’t as difficult as it might seem initially.  A global weakness will affect the player in every situation, so a heavy-handed global weakness will be a constant irritation.  But a specific limitation will only be felt when an element is being used outside its role, which a player can learn to avoid, eliminating the annoyance entirely.  Nobody complains that their fancy sports car doesn’t work underwater, they just stay on the bridge.

[Continued in Balance of Power II]

GDC 2010: Design in Detail II


In order to develop a sense of balance, you need to understand how your brain works. You have an Orbito-Frontal Cortex; It’s called that because it is located behind your eyes, but it’s really your Gut.  When you learn something new, it goes through a process where it builds a model of the world and makes predictions about that model.  If it is right, it releases Dopamine, which cements the model a little bit.

If you are a designer, you need to familiarize yourself with how this process feels, because your ultimate goal should be to get the game inside your head.  You want the model in your gut and the game in the world to be the same.  You should be able to predict how the game will play in a given situation before actually picking up the controller.


Ok, back to Halo 2.  We had to patch, even though we didn’t want to.  Patches are risky and expensive.  Luckily we had network bugs, so we were going to have to patch anyway.  (I’m not sure we would have gotten to patch Halo 2 strictly for balance changes; I’m glad we didn’t find out.)

Choosing what to patch was harder.  You want to tweak everything, but you can’t because then testing gets out of hand.  Games that have the ability to easily change the gameplay often over-patch fopr precisely this reason.

Choosing what NOT to patch was hardest.  We didn’t change the Sniper Rifle because it was right below the line of what we could safely re-balance

Which brings me to my final theme:  Make the hard choices.  Balancing is hard because it requires you to do things you don’t want to.  And it is tricky because there are so many ways to confuse or talk yourself out doing it properly.  But the worst thing you can do is leave the decision up to chance because you can’t make a tough call.


Why are these choices hard?  Again, the answer is your brain.  You also have a Pre-Frontal Cortex.  It’s called that because… Who knows?  We call it your brain.

It is a poor tool, but it’s what we have.  You can’t reason out everything, in fact you can’t reason out very much at all.  There are so many ways that your logical mind has to trick you.  You must confine yourself to reason on the detail scale.  You just can’t hold enough factual information in your brain to make rational decisions about very complex situations.


Radiolab is a great show on New York Public Radio.  They have a podcast, you should subscribe!  In an episode called “Choice” they describe this experiment where psychologists give people a number to memorize, 2 digits to 10 digits.  Then they send them to another room to repeat their number.  On the way, they have someone interrupt them (All good psychological tests are about fooling the subjects) and ask them if they want an Apple or some Cake.

The people with short numbers pick Apples at a high rate; Apples are better for you, fewer calories, watch your waistline.  Those trying to remember longer numbers more often choose Cake.  They are so busy with numbers, they make the decision emotionally.

That’s right, 7-10 numbers are enough to completely fill your rational brain!  My high school calculator had more horsepower than that!

So when you have to think rationally, think about details or you will get hopelessly lost.  And fat.


Ok, here are the four themes of my talk:
– Balance is longevity
– Balance in passes
– Develop your sense of balance
– Make the hard choices

I am going to use these themes to explore the Detail.  Now let’s get to the Sniper Rifle!

[Continue]

GDC 2010: Design in Detail


Ok, so when I gave this talk at GDC I didn’t have time to finish, even though I was talking very fast.  I did better when I gave it at Blizzard, until my voice ran out and I could barely speak.  So I probably should have cut some ideas out and saved them for this year.

I do see the irony of failing to trim a talk that advices designers to drastically reduce the scope of their game as early as possible.  But to me, the value of GDC has always been that it makes me think about my own problems from a different perspective and inspires new ideas as I listen.  So I wanted to cram as much idea-fodder into the talk as possible, not produce a fluid, polished experience.


I did not make the call on the Pistol, I didn’t even know about that call, it was made directly to the cache file after everything was supposed to be locked down, in fact… but I’m not bitter about it.  I did decide to give the BR some spread, which has been the topic of much debate.  Luckily Reach has been even more controversial, so nobody remembers it anymore.  It’s interesting that every single Halo game has had major controversy over the MP starting weapon, I bet you could write an interesting talk about that.


In 2009 I was at the Art Institute of Chicago visiting my family.  (I grew up in and around Chicago.)  I saw one of the most famous paintings of all time and took a picture of it with my phone.  I actually did have the idea for this talk at exactly that moment, at least vaguely.  Any guesses as to the painting?


It’s “A Sunday Afternoon on the Island of La Grhand Zhot” by Zhorzh Soo-rah (I really wanted to pronounce his name right…heh)  This painting inspired my talk (and its very long title)  Still don’t recognize it?  Here it is from a little farther back.


(I showed you the part in the lower right by the monkey)
This painting isn’t famous for how it looks, or what it shows, but how it was made.


Seurat lived in the 1800’s.  He was very interested in how we perceive color.  Scientists were just discovering that what we see as one color is actually a mixture of different colored light.  To demonstrate this fact, he invented Pointillism, the artistic process of using tiny dots of basic colors to produce an image.  The same way your printer does.

There is a really great play called Sunday in the Park with George that I recommend you see if you are interested in learning more.  You can skip the final act, though.

So I started thinking…  What happens if we take Halo 3 and break it into it’s tiny details…


And analyze just one of them.  Take one tiny Decision, and explore it exhaustively.  Specifically, the time between shots for the sniper rifle.  (I had a lot of fun putting together the pictures for this slide deck.  I never tried to pointilize a screenshot before.)


So here is the actual title of my talk.

If you have been to GDC, you know that most of the talks are too broad to be really interesting.  It doesn’t get much more specific than this!  (Of course, I took this narrow topic and used it to explore lots of subjects and theories, but still…)


My opinions may not represent Bungie management.  In fact, I know they don’t.  (If I only knew the irony of that statement at the time!)  My opinions may not represent reality; this is the past as I remember it, but as we will find out, brains are not reliable.  All examples, even negative ones, are from good games.  I tried to pick on games that everyone knows are great, to avoid controversy.

This talk was really hard to write! Really hard. The more specific the topic, the more there is to say.  It ballooned to almost 300 slides, editing took forever (and it turns out I still didn’t edit it down enough!)


First, some context from Halo 2.


Halo 2 wasn’t just popular, it was popular for years and the Sniper Rifle remained balanced the whole time.  It never needed to be changed, limited, banned, it was still fun.

This can give us a practical definition of Balance:  Balance is Longevity.


(X= 3, I told them my talk would appeal to Engineers!)

Balancing an equation is a process.  But game balance is a state that either exists or it doesn’t.


The 4th rule of Jenga makes it clear (say it with me):

4. Your turn ends 10 seconds after you stack your block

It isn’t balanced unless it lasts.  (I bet you didn’t expect to see a Jenga reference!)


There have been other talks about Halo 2’s crunch; I’m not going to re-hash them.  My really quick personal post-mortem:  Don’t set yourself up to try and fix bugs in the Tutorial and balance the Weapons at the same time, It’s not going to work.  At least not without wrecking your personal life.

Production is always worried about a repeat.  (As you can tell during this talk, Production and I have a love-hate thing going.  It is mostly a joke, but Deisgn and Production have very different goals and the game is only going to work if they cooperate.)  They were always asking me when I am going to be done, so I invented the Balancer’s Paradox.

Balancer’s Paradox
– I can’t balance the Sniper Rifle damage until we set the Player’s health
– I can’t balance the player’s health until we know the engagement distance
– I can’t balance the engagement distance until we set the Sniper Rifle damage.

But after using this for awhile, I actually had to invent a solution…  Balance in passes.  The Sniper Rifle always has to be balanced! You could ship at any time!  So you keep it balanced all the time.  But there’s balanced, and then there’s balanced…


At the end of each pass, the game is balanced to a certain level.  Once a game is balanced to that level, do not backtrack.  Basically, what this means is that if you have balanced the strength of a game element, don’t make it weaker in order to limit the roles of that element.  Unless you have to, of course, in whic case it will impact the schedule so you need to let Production know.

Halo 3’s Balance Passes are listed here.  I think they would work for most games.  They match with stages of game development and I’ll go over them in more detail later.


Remember: Balance is Longevity.  And we could tell by playing it that it wasn’t going to last.  We all had the same feeling and we didn’t really doubt it.  But how did we know?  We had developed our sense of balance.


In Outliers, Malcolm Gladwell lays out his 10,000 hour rule.  This makes me the world’s only expert in trying to balance the Halo Sniper Rifle.  Sort of a narrow expertise, I admit.

Niels Bohr offers this definition of an expert.  This also makes me the world’s foremost expert in trying to balance the Halo Sniper Rifle (and in Driving too Fast for Conditions.)

But what are time and mistakes? They are just experience.  So why is experience so much more important to being an expert than training, knowledge or talent?  Because of how your brain works.

[Continue]

Case Study: Tribes

Previously, we have explored how the community balances a game, sometimes despite the developer’s best intentions.  Tribes is a great example of how the community not only determines how the game is ultimately played, but often decides the path of future development.

Tribes shipped in 1998 to a fair amount of critical and commercial success.  It featured large multiplayer battles on open terrain that were beyond anything that had been seen before.  Players could choose between three armor classes (Heavy, Medium and Light), pilot vehicles, plant bases, purchase weapons and equipment… it even had jetpacks!  It also had one very significant bug, an unintended side-effect of the physics system known as “skiing”.

That flag is on fire because it's sweet

Go Zebra Tribe!

By tapping the jump button while descending a hill, players could exploit this physics bug to accelerate to an incredible speed.  Combining this technique with the jetpack would allow players to quickly cross even the largest maps, much faster than the designers anticipated.  This worked even with heavy armor, meaning there was little incentive to choose the lighter, more agile classes.  It was faster than vehicles, making them redundant.  Since most of the weapons did not have instant travel projectiles, it became almost impossible to hit anyone outdoors.  Nearly every aspect of the gameplay was affected.

In a short time, the game balance was totally wrecked… and the players loved it!  They invented new strategies, found new ways of attacking bases, used old weapons in new ways.  They became experts in using another physics bug called “body blocking” to physically bar enemies from escaping with their flag.  The chaingun, a weapon that had been scorned, became their weapon of choice because it fired one of the few projectiles fast enough to hit a skiing player.  They re-balanced the game around this new game mechanic.

Speaking of unexpected effects...

The Tribe has spoken.

The developers attempted to fix the game with a patch, but the community rejected it.  By that point, everyone who did not like the effect of skiing had already left the community.  The remaining players where those that thought it was fun.  Unfortunately, this smaller community was the only audience for a sequel, so the development team were forced to cater to them.  Tribes 2 not only included an “official” version of skiing, but even explicitly taught new players how to do it!



Takeaways:

  1. Don’t just test for bugs, but to ensure the gameplay experience is the one the designers intended.
  2. The ultimate balance of a game lies in the hands of the community that plays it.
  3. Fun activities are rare, and when we find one (even as the result of a bug) we ought to embrace it.

Tripping over the Starting Line

Running is risky.  Your center of mass is so far in front of your feet that you are constantly falling forward, catching yourself with each stride.  You appear to be in control and stable, but in reality you are always one misstep away from catastrophic failure.  (Thoughts like this are why game designers are rarely world-class sprinters.)

QWOP

Ready!

During development, a game can appear to be balanced, but is actually just being carried along by momentum; the instability is masked by constant change.  Releasing the game at this point is like tying a runner’s shoelaces together.

QWOP

Set!

When the designers cede control to the community, they quickly find the truly balanced state.  Unfortunately this often results in a degenerate or random experience where entire gameplay modes are untouched, fundamental mechanics no longer have an impact, and usually the game becomes too simplified to remain interesting.  Even worse, developers are often forced to incorporate the broken mechanic into a sequel or risk alienating their fan community.

QWOP

Trip!

How does this happen?  Often it is a result of a flaw in the development process.

Unenforced Conventions

Early in development, when the game is being prototyped, it seems inefficient to rigorously encode the game mechanics.  It is easier to just ask playtesters to refrain from using certain tactics, ignore logical loopholes, and pretend the game works in a different way than it actually does.  After all, the playtesters are usually on the development team, and the prototype changes faster than the code can be updated.

The problem comes when these conventions become so firmly established that the designers start making assumptions about what the community will do based on those (false) expectations.  When the game is released, the community does not respect conventions, they will exploit any tactic or loophole the game allows, ultimately breaking the balance.

Isolated Game Systems

A common production tool is to organize features into prioritized lists, with the understanding that everything below a certain line has a chance of being cut.  This encourages designers to create isolated game mechanics, parallel systems that do not interact with one another, so that the inevitable cuts have less impact on the surviving mechanics.  These layers are frequently worked on by different designers with different goals and ideas about what the game should be.

This leads to the situation where game systems are individually balanced, but in differing, or even conflicting ways.  The progression mechanics that keeps player invested in the community might break the competitive multiplayer game.  Or large sections of an environment may go unused because of the way the mission objectives are placed.  Usually, the most poorly balanced aspects of the game drag down the other systems, leveling any interesting nuance they might have had.

Ignoring the Skill Zenith

Designers are rarely as good at the games they develop as the people that play them.  (They tend to spend more time building them than mastering them.)  It is often their ability to sympathize with the “average” player that makes them good at their jobs.  Unfortunately, this means that they have a blind spot and cannot always predict how the game will be played at the very highest level of skill.

Nothing wrecks game balance as fast as a community that is more skillful than the developers anticipated.  Actions that were meant to be impossible or happen only through luck become fundamental to the game.  The community is split between those that can execute the “impossible” tactic and those that cannot, and are no longer competitive.

No game ships with flawless balance, but by avoiding these pitfalls your game community may last long enough for you to tweak it.