Diablo 3's Ability System

Diablo 3 comes out in a couple weeks. I'm giving it the coveted award for "Biggest Comeback In System Design." Diablo 2's ability system was so bad that it's almost unbelievable, while the way Diablo 3 handles ability customization is one of the very best systems I've seen.

Diablo 2

Diablo 2 had talent trees where you spend points to unlock new abilities, very similar to how talent trees work in World of Warcraft. Also, you could allocate stat points into various different stats however you wanted as you leveled up. At first glance, these seem like ok things, but let's look at just how deeply problematic they really are.

Don't Use Points!

First, the best way to play Diablo 2 is have this big red "+" button on your screen almost the entire time, the one that says you have extra points to spend. The reason that will be on you screen for weeks is that you'd be a sucker to actually spend the points as you get them. You counter-intuitively (and unfunly) should stock up on those and spend them much later on. So the simple and fun thing to do (spend points as you get them) is just a trap for noobs.

Next, the whole system of allocating points in the first place didn't really customize anything. It was just a giant test of if you did your web research enough to know the only reasonable way to spend those stat points. You don't have to take my word for it either, let's see what Jay Wilson has to say. He was an avid Diablo 2 player, and the Game Director of Diablo 3 for the last 5 or 6 years.

Here's a written transcript of the relevant part, in case you don't want to watch the vid:

"You usually take as much strength as you need to get the armor that you're targeting, and that's usually around 120 or 220, depending on what type of armor. You take 75 dexterity because that's the amount you generally  need for good block percentages. You take NO energy at all unless…there's like one type of build you can make on a sorceress that uses energy shield. And then you put everything else in vitality. That's a shitty customization system. That's just not a good system." --Jay Wilson, Diablo 3 Game Director on Diablo 2

Talent Trees

Next, there's the talent trees. There's two problems here, one medium sized and the other is one of the most mind-blowing fumbles in design out there. First the medium problem: it's pretty hard to make talent trees that give any real choice. They sure seem to allow choice, and in theory they really could, it's just very hard to balance it all so that there's a lot of good builds. Blizzard learned this in World of Warcraft, and I think we can see a clear progression in their thinking here. The first thought was that talent trees are great (and I was on board with this). Then there were too many talents that were "required" because they were so damn good, you couldn't pass them up. Stuff like +5% damage, you just have to take that compared to various utility skills. Blizzard reworked all the talents (well several times, but I mean one time specifically) to get rid of all those "required" talents. If something was just +damage, they mostly got rid of it as a talent. If a talent was an ability that was *necessary* for a class, they just gave you that ability outside the talent trees. So now what was left allowed for more flexibility in your choices.

I was on board with that, but it kind of didn't work that well in practice. Blizzard then gave it yet another try, trying to open up the reasonable choices even more. The next step in their progression in WoW talents was to get rid of the trees entirely, for the Pandaria expansion. In the new system, you will pick one of three possible talent powers every 15 levels. (Here's the Warlock one, for example.) Diablo 3 takes an even further step in this progression, but let's come back to that. There's one more thing about Diablo 2.

Start The Entire Game Over To Change Even One Damn Talent Point WTF

In Diablo 2, you can't respec your talents. Just think about that for a minute. If you spend a talent point wrong once, you have start over your entire character. What? Yes, really. If you want to try out a new ability and see what it even does...you have to start over your entire character. This is completely ludicrious. The best way to play the game is actually to download a hack that lets you set ability points to whatever you want instantly, just so you can see which build you might want to play, then go back to the real game. I've seen many players defend the lack of respec as "replayability" but that's not what replayability actually means. That's just an enormous time sink for no real reason and it severely damages the play experience. (Note that 9 years after Diablo 2's release, there was a respec thing you can do, if you jump through some hoops. Too little, too late.)

Years ago I saw several official Blizzard posts that defended a similar idea in World of Warcraft. Their claim was that the intentional difficulty (and originally, the complete inability) to respec talents was to create more diversity, and to make choices matter. This is really wrong-headed and actually the opposite of true. If you have a balanced system, you would not have any need to prevent everyone from switching their specs around. You're basically saying that you're happy that a lot of people are locked into bad specs they aren't happy with, because that means there are more different specs out there being played. What a terrible thing to inflict on your players. Again, you'll have varied specs out there if you actually have several viable ones and small or zero switching costs. Imagine if we made a fighting game and "balanced it" by saying you are stuck with whichever character you first pick! The big variety of characters played shows how great our balancing is right? (No.)

The no-respec mindset is actually counter-productive to the goal, too. When switching costs are really high (like creating your entire character over from scratch...) then no one really wants to experiment. It's too risky to do so, and it's better to go look up the cookie cutter build and go with that. So you get less variety, not more. The variety you do get is often from players who you pissed off by punishing them for mistakes or for exploring the system.

The good news is that Blizzard's thoughts on this have clearly changed over the years. WoW respecs got more permissive over time, and the next step in that progression is Diablo 3.

Diablo 3

Allocating stat points as you level up: gone. Great, this was busywork that contributed basically nothing, so the subtractive design makes the game more elegant overall.

Talent trees: gone. You have exactly 6 slots for abilities, and you can put whatever you want in those slots. There are approximately 24 abilities per class, so your build involves making meaningful choices about what to keep and what to leave out.

Runes: interesting new feature. I read that this system took far longer to design than any other system in Diablo 3, and I totally believe it. When I first saw the interface in the recent open beta test, I couldn't believe what I saw. I was so blown away, that I had to go read about it before clicking on anything because it appeared too good to be true. I think this actually happens a lot in design, where when you finally create / see / experience the "right answer," it seems so obvious, like it couldn't have been any other way, but it might have taken years for the designers to figure out that answer. Elegance is hard.

Here's how runes work. A rune is a modifier to an ability. Every ability (each of your class's 24 abilities) has 5 runes associated with it. And I don't mean the same 5 choices, these are custom for every single ability. You can only have rune selected for any given ability. So that means you have to choose if you want your Magic Missile to have 1) increased damage, 2) split into three shots instead of just one, 3) pierce through enemies and keep going, 4) generate mana ("arcane power"), or 5) track the nearest enemy and do slightly more damage. Here are the abilities for the Wizard, along with all their possible runes.

So the combination of possible builds here is ridiculously large, given that you fill each of 6 slots with one of 24 abilities AND for each of those 6 abilities you chose, you also choose one of 5 runes. Oh and you also choose any 3 out of 15 possible passive abilities for you class, so even more combinations.

Infinite Instant Free Respecs

Now here's the part that was too good to be true to me. You don't spend points on these runes. You don't muck around with them in your inventory. You don't commit to them and have to pay some annoying respec fee or something. At *any time* you bring up the ability menu, set which abilities you want, and for each one click on the rune you want. It's all in a nice menu with no hassles. Again: any time. With no cost. As much as you want. The only drawback is a three second cooldown so you don't do this in the middle of a fight. Wow!

As you level up, you automatically gain new abilities and runes. Gaining them requires no action on your part. And at any time, you can switch amongst any abilities and runes you have so far, eventually all of them. You can fully explore the system all you want. You can see what every ability does. You can try out any combination of abilities. The freedom is amazing and it shows newfound confidence from Blizzard. There is no need to slow the progress of people figuring out good builds: Blizzard is telling us that exploring builds basically *is* the game, so go for it.

Elective Mode

I do have one minor complaint here. Internally, Blizzard said they divided the abilities into different categories that helped them think about what's what, then they realized that players should be able to see these categories too. So they exposed them, and tied them to the 6 different slots you have. I think this worked really, really well. It makes the whole system easy to understand, elegant, and imposes an interesting restriction: that you can only have one ability from category one, one from category two, and so on. It would be absurd to think you don't have enough choices, because you actually have over 29 BILLION possible builds per class with that system.

But really, I think Blizzard had already done a lot of development that assumed you could choose multiple abilities from a category if you wanted. They were maybe already too far down that road. So while their new system is easy to understand, elegant, and has an interesting limitation, you can turn on "elective mode" in the menus to get a less elegant UI that lets you put any ability in any slot. And of course you have to because it's strictly better for you to remove that limitation. So yeah, too bad they couldn't have made the simpler concept with better UI and the category limitation work. But whatever, it's fine.

Nephalem Valor

There is one more surprisingly great thing about the Diablo 3 ability system. That you can respec at any moment as much as you want does create one problem. If you are super hardcore, you will have a different spec for like every encounter in the game once you have memorized it all and are farming for items. That means the best way to play is tedious once you reach that level of mastery. It would really suck to "fix" that by limiting the respec in any way though. Normal humans want to explore the system freely and I'm so blown away by this infinite, instant, free respec thing that we should NOT ruin that to address this hardcore problem.

Of the top of my head I thought, "Hmm, maybe have a separate mode where respecing sucks or something, let hardcore people play that." But Blizzard's answer is much better. The Nephalem Valor system kicks in at the max level (60). So before that, meaning your first run through the game, you really can respec all you want for free with no drawback at all. Go for it! Once you reach 60, you can get a buff called Nephalem Valor that can stack a few times, maybe up to 5. Each buff increases your gold find / magic find stats. Also, if you kill a boss with that buff on, the boss will drop extra loot. You get the buff by killing rare or champion monsters.

The genius part is actually how you lose the buff though. I think it lasts about 15 minutes, so you have to keep progressing to stay buffed. But you also lose it if you *leave the game* or if you *change your abilities or runes at all*. Ok think about that. If you plan to farm the same 3 minute segment of the game over and over and over, you can do that. But you'll be doing it without the buff so it won't be optimal to get rare items that way. Also, if you want to respec before every single encounter, you can. It's just that you won't have the buff so it won't be the optimal way to get items either. The optimal way to get items happens to line up with the fun way to play: to go an entire big run where you stick to one spec. This is a very clever way to solve the problem for the new player and the expert without really sacrificing anything. 

Conclusion

Thanks to Jay Wilson and the rest of Blizzard. I think this ability system with 6 slots, the lack of tech trees, the 5 runes per ability, the infinite instant free respecs, and the valor buff system overall is a very solid design. I'd go so far to say that it advances the craft of game design, even. Blizzard has come a long way in designing these kind of systems, and I think they've finally nailed it.

Comments

[Sirlin]

Playing Puzzle Strike instead sounds good, but the Neph Valor buff really does do what it was supposed to. You wouldn't give up your stacks just to change skills if you're actually trying to be efficient, which is sort of the point of the game.

[Stephen Keller]

I'm a little confused by EricF's post... is this really how people are playing Inferno now? I stopped playing around the time 1.03a came out, but glancing at the patch notes it doesn't look like they've really done any major tweaks since. I can say that at least in early July, as a barbarian, there were a number of very workable builds for Inferno and lots of discussion on the barbarian forums and blogs as to optimal playstyle, suggesting there wasn't a clear cut "Do this to win." Barbs weren't gearing solely for DPS, and in fact the big argument was always around how much effective HP to give up in order to take increased attack speed or (after the IAS nerf) +crit %/+crit damage. Also with 1.03, all three major gearing methods (dual wield, sword-and-board, two-hander) were viable again in Inferno. So it seemed like there were lots of options.

And, EricF, did you actually play Inferno that way, ignoring NV and constantly switching skills? The argument that "loot isn't good" is not really true at all, since Inferno is entirely about getting loot. Most loot isn't good, but the few pieces that are good are/were really, really valuable. At the time I quite, gear with good stat distributions was inflating massively, with really good weapons selling for 10-100m when they were only worth a few million two weeks earlier. Dropping NV drastically reduces your chance of getting good drops, when the whole point is to get good drops. The guaranteed minimum 2 rares off a boss with a stack of 5 NV (introduced around the same time) is also a very strong incentive to always have full NV when fighting bosses. Yeah, most of the time those rares are crap, but you need to do whatever you can to maximize your exposure to the RNG to increase the chance of getting the good stuff.

Switching gears... Sirlin wrote: "That's the whole point of Diablo3 though, to be a Skinner box, lol." I think this is fairly true of Diablo/Diablo 2 but I really think Blizzard tried something different with D3. Like I said earlier, it feels like they tried to add in an MMO-style progression to the endgame. It's easy to write off MMOs as just being Skinner boxes as well, and they certainly rely on those mechanics, but anyone who's ever done progression raiding knows that finally downing a hard boss after weeks of trying has a sense of satisfaction that is way beyond just "Oh I got something shiny."

Actually, Sirlin, it was you who sort of made me think about this during one of your posts about achievements. If I recall correctly, your argument against achievements is that external motivators to accomplish goals are counterproductive, because real motivation is internal. Yeah, people will do stuff if you give them external rewards, but they won't like it as much as if they were doing it of their own volition. I think you then tied this back into the idea of mastering games as a sort of self improvement, e.g. getting really good at a competitive game is its own reward because you feel like you've accomplished something meaningful. (Hope I'm paraphrasing you correctly.)

This idea was one of those that really stuck with me; one of those things that as soon as I read it I realized it was true and even a little profound, with a lot of implications beyond just achievement systems. Let me suggest that "get loot for clicking a lot" is akin to the ugliest achievements ("Do boring thing X number of times"), in which you're "rewarded" by the game for doing some repetitive nonsense. I think we can trick ourselves into thinking we like these even when we may not -- more than once I've found myself trying to accomplish some task in a stupid game only to realize that I wasn't having any fun and didn't really like the game anyway. So why was I trying to do it? Well I wanted that reward! The first two Diablo games really mastered exploiting psychology in a way to keep you playing, even when that playing was often dull.

Contrast this with the work that goes into downing a hard raid boss in an MMO. It takes a lot of time (and unfortunately a lot of grinding to get to the point where you have the level/gear needed to seriously attempt the challenge), just like getting good loot in Diablo 2, but there is a different texture to the feeling of achievement. When I think back to the hard stuff I've beat in WoW, I feel genuine accomplishment because it represented a lot of work, strategy, thought, discussion, and coordination with other people. I really felt like I mastered some aspect of the game. Finding a great item in a roguelike? No, I can honestly barely even remember most individual instances.

The pattern that I think Blizzard wanted us to follow in Inferno was some kind of hybrid MMO+Diablo. There was the random loot grindiness from Diablo (for some reason they doubled down on randomness which seems to have been a pretty big mistake), but a very deep skill system that tied in with your builds. They also introduced major bosses that actually do require skill to beat, and in fact they're clearly modeled on WoW bosses with many of the same mechanics (don't stand in fire, avoid this attack, different phases, enrage timers, etc.). They wanted us working hard to get *good* at the game by mastering the skill system and also mastering boss fights while grinding out gear to progress. People don't seem to have liked this -- see the complaints about enrage timers -- but I think it was an interesting idea.

I think there are some really interesting mechanics/game design elements that non-MMOs could steal from MMOs, but unfortunately they just steal the bad ones (yay we can grind for XP/loot in every single game now). But a single-player game (or small, enclosed multiplayer one like D3) that offered a facsimile of progression raiding could be really, really interesting. Single-player games don't really seem to offer many interesting challenges these days (that has been replaced with awful achievements), but the hassle of having to play an MMO constantly plus coordinate your schedule with 9+ other people makes raiding a real drag.

So that's part of my disappointment with how D3 was received. There were a bunch of interesting ideas trying to break modern action RPGs out of the Skinner box model that D2 so perfected, but maybe they didn't go far enough or maybe they shouldn't have called it Diablo, because the reaction seems to have been "We want our Skinner box back!"

[EricF]

It's possible that more recent changes have outdated my comment - I only a little when it first came out, but quit due to (my) perceived emphasis on uninteresting grind without reward.

[Sirlin]

Recent changes didn't outdate your comment. It never at any point made any sense to play how you're saying. Losing Valor buffs on purpose makes no sense to do, and I've never even heard of anyone doing that. Saying that "items are bad" is no kind of support reasoning either. You want items and you need gold/magic find to get better ones, so losing those stats is punishment enough that it's more efficient to keep your stacks. This whole side topic is some bizarre derail that applies to basically no one.

Stephen, yeah good post but I think you kind of oversell the idea that the Diablo progression is sort like raid progression. Yeah true and I know what you're saying. It's just that...that's some kind of minor footnote rather than an interesting point. I mean the game is entirely a grind, that's what it's all about, and our judgment of it should really only change by like 1% or something due to the raid progression idea. It's just...a natural consequence of everything else. It sort of had to be that way because they want to it to last longer, so they made it increasingly gear checky towards the end. They also made player-skill matter too little relative to the gear check, and they pretty much know that as reflected by getting rid of some of the stupider combinations of elite powers.

Also, "we want our skinner box back" doesn't even seem like a valid complaint. This game is skinner box to the max, so what the heck. I still think the real issue is "we don't like new things. If those new things are super duper skinner boxes, that's beside the point. WE DON'T LIKE NEW THINGS. You know how it kind of sucks the way talent trees were before? Well we don't care if that's better. Because it won't be the same. We seriously just want it to be the same. If you give us something different that is better in 99 ways and worse in 1 way, we will only post about the 1 way it's worse. Why? Because we don't like new things. Old, old, old." That is the vibe I get from an overwhelming number of posts.

And just to be super clear, I totally agree with Stephen that the tuning in Inferno could be a lot better. It all makes a bit more sense in patch 1.4 than before, at least. So while we could have a whole lot of complaints, they wouldn't be complaints like "we want our skinner box back," or "it sure sucks being able to choose which abilities we want each session." Real complaints are like "the crafting system should really be like Path to Exile where you can reroll a stat or change a stat to a different stat, so literally several orders of magnitudes more items will be potentially useable." Or maybe "it's just weird that bosses are easier and give worse loot than random elite packs, no matter how you try to sell that." Or "ability tuning should be better so that there are more viable builds."

The only ability-system complaint I can really think of, which I'm on the fence about if I have this complaint or not, is the thing I raised in the original article here. I wonder if each slot should have 5 ability choices, like it has to be one of the 5 that go in that slot. Reason against that: it's fun to be able to build anything you want, so it's cool there is no such restriction. Reason in favor: as mentioned in my post about SCG4, more choice can be illusion as it means a more and more fragile system, more likely to degenerate into some optimum combination. Limitations on what goes in a slot might have allowed for even more viable builds, if the game had been designed around that idea, but it wasn't so oh well. And I'm not sure it's a problem anyway with good enough tuning of abilities.

[Ivo]

Sirlin, I'd be interested in knowing your design opinions on Torchlight and Torchlight 2.

I'm really glad that Torchlight lets people play single player "offline" and such, but that is another story.

I was a bit sad to know that they (predictably) keep the "old" system of making new characters to re-roll skills (apparently you can change the last 3 points assigned, but that is it). That does seem to be a major step back in terms of good design (to me at least), but it seems lots of people prefer it that way.

I think if one plays exclusively single player, "locking skills" isn't so bad if the game is balanced properly for it - from my own past experiences a most of the enjoyment when doing single player is restarting and playing through the early levels rather than doing end-game grinding. But it still sucks that you're forced to do that instead of just having it as a choice, and that you can't try different high-level skills without paying a big time penalty.

Ivo.

[John Costello]

There is a place in D3 where you get "invested" in a build, and that is the gear. Although you can mix and match abilities with no penalty, it seems to me that at higher levels people specialize their builds so that their gear stat choices reinforce their build choices. And at the very highest level, good gear costs so much that you can't have two sets of gear where one is good for (say) a kiting-based build while the other is good for a tanky melee build.

It seems to me that the gear system in D3 is really broken; the reasons have been touched on by others in the thread, but I would sum up by saying that it looks to me to have been designed to put money in Blizzard's pocket foremost, and so it's not surprising that it's not very much fun.