WoW: PRESS ALL THE BUTTONS! Convergent Design in Class Mechanics

In many MMOs, WoW being a very prominent one, there’s the idea that classes should be relatively unique. I mean, what’s the point of playing a Priest if the class feels like playing a Mage, but with white spell effects rather than blue, right? But at the same time, there are a lot of factors that create tension with that concept.

One is ensuring all classes have the same base toolkit so they can solo effectively. Everybody needs an interrupt, some sort of minor self-healing, a defensive cooldown, an offensive cooldown to be able to burst DPS, and so on. It still leaves a fair bit of wiggle room as far as design space is concerned, but giving all of those tools to each class definitely reduces the disparity across classes.

Another concept is the idea of convergent design. As you iterate on different designs and pull in concepts that work from other classes, and discard the ones that don’t work, you’ll approach an ideal set of mechanics if any such ideal exists. Now, ideal in this case is somewhat subjective, but at the same time, there’s a few cases where objectively you could say a mechanic just sucked.

One such example is the Retribution Paladin class from Wrath of the Lich King. When building a set of player-based mechanics, you need to introduce some kind of limiter, a resource of sorts, otherwise the player will just spam the highest damaging (or healing) ability (See: Arcane Mages). In first-person shooters, often ammunition is the limiter. For Retribution in Wrath, cooldowns were the limiter. When you use an ability, it goes on “cooldown” such that you cannot use it again for a period of time. Some abilities may go on cooldown for a few seconds, while others may be minutes.

The issue with Retribution in Wrath, however, was that there were not enough abilities to use to fill in the space between cooldowns, such that the class devolved into “First Come First Serve”: if an ability was off cooldown, hit it. Otherwise, wait. You could throw every attack you had onto a single macro and spam that button, and achieve near-max DPS. Hence the nickname “lolret”. You could pretty much literally faceroll your way to victory, which is clearly a failure in class design. That’s not engaging whatsoever. (See: http://korecsguidetoret.blogspot.com/2008/04/how-to-retribution.html for an example of just how... empty the Retribution rotation was in Wrath).

With apologies to Allie Brosh

Now, at the same time as “lolret” was occurring, Enhancement Shamans also got a makeover. Their new mechanics used a “Priority System” as the primary resource rather than mana/focus/rage, which is to say you’d often have multiple abilities off cooldown, and each ability has a priority. Higher priority abilities should be used first, and you’d need to re-evaluate what abilities are off cooldown each time you used an ability. Now, you could reduce this to a single button same as Ret, but Enhancement also had a little bit of extra sauce where multiple abilities were placed on the same cooldown, and you had to make a judgment call on which ability to use: Flame Shock vs. Earth Shock (or Frost Shock), Searing Totem vs. Magma Totem, and Lightning Bolt vs. Chain Lightning. (See:
http://wow.joystiq.com/2011/06/04/totem-talk-state-of-the-enhancement-shaman-address/ for a bit of history here).

The difference is subtle, but important. Both classes used cooldowns, but not having enough buttons made the class too simple, and having too many buttons (ye olde Feral Druid) would make the class obscure and not fun except to the most masochistic of players. There was a balance to be had there. And if you didn’t include branching in your rotation, then you could reduce the rotation to a single button, regardless of how many buttons you had.

(Simplified) Feral Druid Rotation Diagram from days of yore.

Fast forward to today, where Blizzard has learned these concepts and applied them. Funnily enough, Enhancement has changed very little since Wrath, with the exception that damage has been spread to active abilities rather than in auto-attacks and auto-procs. If anything, Enhancement has become more complex, with the addition of Unleash Elements and Lava Lash spreading your Flame Shocks to increase the amount of interplay between your abilities.

Retribution, however, is looking a lot like Enhancement Shamans these days. Retribution now has a full-out Priority System, with multiple abilities sharing cooldowns to ensure you have to make decisions on the fly. They both have a finisher-based resource system, too.

Quick note, a useful tool in Computer Science, and mechanic design in general, is abstraction. Basically, divorcing your discussion from flavor and boiling it down to the base components allows you to more easily compare your Granny Smith to your Red Delicious: in the end they’re both apples, and that’s the important part. But of course, you want to make sure your abstraction is correct for what you’re doing, and not too abstract, or you’ll lose the essence of your conversation. For example, Ret and Enhance are both Priority System classes, but all classes are Ability-Based classes. The former is a useful abstraction, whereas saying all classes use abilities is not a useful abstraction.

So let’s compare the two:

Retribution	Enhancement
Priority System Multiple abilities off of cooldown simultaneously	Priority System Multiple abilities off of cooldown simultaneously
Mana-Based But Mana regenerates so fast as a part of your normal rotation as to only be a limiter if you’re spamming heals.	Mana-Based But Mana regenerates so fast as a part of your normal rotation as to only be a limiter if you’re spamming heals.
Secondary Resource: Holy Power. Gained on ability usage. Funds finishers (Divine Storm, Templar’s Verdict). Also can be used for Healing (Word of Glory). Used for DPS maintenance (Inquisition). All-or-nothing. Using partial amounts either not generally beneficial, or not possible.	Secondary Resource: Maelstrom Weapon Gained on melee attacks at random. Gained on ability usage at random (Stormstrike, Lava Lash). Funds finishers (Chain Lightning, Lightning Bolt). Also can be used for Healing (Healing Surge, Healing Rain, Chain Heal). Using partial amounts can be beneficial.
Rotation Branching Templar’s Verdict vs. Divine Storm vs. Inquisition Crusader Strike vs. Hammer of the Righteous Seal of Truth vs. Seal of Righteousness	Rotation Branching Earth Shock vs. Flame Shock (vs. Frost Shock) Lightning Bolt vs. Chain Lightning Magma Totem + Fire Nova vs. Searing Totem
DPS Maintenance Inquisition once per minute	DPS Maintenance Searing Totem/Magma Totem once per minute
Ability Interactions Exorcism, Crusader Strike, Hammer of the Righteous, Judgment, Hammer of Wrath -> Holy Power	Ability Interactions Searing Totem -> Searing Flames -> Lava Lash Stormstrike -> +Crit for Lightning Bolt, Chain Lightning, Earth Shock Unleash Elements -> +30% Fire Damage -> Flame Shock, Fire Nova Lava Lash -> Flame Shock Stormstrike, Lava Lash -> Maelstrom Weapon Flame Shock -> Fire Nova

So looking at the two, they play quite similarly, with the exception of utility, where a lot of the flavor lives. Paladin Hands versus Shaman Totems. How the different abilities interact is also a major difference. For Retribution, it largely doesn't matter what order you use your abilities in, because they don't interact with each other. You just pick whichever one does the most damage that's not on cooldown and away you go. Enhancement, however, has an amazing amount of synergy between all of their abilities. This does make the Priority System for Enhancement a bit more rigid, however. Use the abilities in the wrong order, and you'll hurt your DPS pretty significantly, whereas Ret doesn't really care too much.

Now, there are subtle differences between Holy Power and Maelstrom Weapon. For example, Maelstrom Weapon is technically random, so if you get a particularly bad streak of procs, you may be stuck waiting for your Lightning Bolt (or heal), whereas Holy Power is like clockwork. Holy Power also allows you to perform finishers nearly back-to-back, with only a single GCD in between, whereas Maelstrom Weapon is technically not needed for Enhancement’s finishers. It just makes them cost no mana and cast instantly, and even a partial stack helps that out.

In the end, though, they feel pretty similar when you’re in the thick of things, but overall it just feels like Retribution is a poor man's Enhancement. The skill threshold to get the most out of Ret seems to be way lower than Enhancement's (which may be why I like Enhancement so much more).

If I knew more about Rogues, or Feral Druids, I bet I’d be able to see a similar comparison. But it does feel like these Priority Systems with Branching are the natural evolution of MMO rotations, and we are seeing convergent design in action here.

Blizzard has been talking about paring down the number of buttons on people’s action bars, and I’ll be interested to see how they manage this without destroying rotations in such a way that we’re back to the “lolret” design. Removing too many buttons means you now have a “First Come First Serve” rotation, and can just make a macro with all your abilities, and removing branches also has a similar effect, though I suppose one could make the argument that branches have the greater effect here, but not enough buttons means you have big gaps in your rotation, and that can often feel “clunky” in the Ghostcrawler sense, because not hitting buttons for 5 seconds is really, really not fun, though having the occasional 1.5 second gap allows you to throw in utility or off-healing.