The MoP Warlock: The Impact of a Novel Resource System in the Gaming World

Alexander Brazie

Alexander Brazie

Alexander is a game designer with 25+ years of experience in both AAA and indie studios, having worked on titles like World of Warcraft, League of Legends, and Ori and The Will of The Wisps. His insights and lessons from roles at Riot and Blizzard are shared through his post-mortems and game design course. You can follow him on Twitter @Xelnath or LinkedIn.

Game: World of Warcraft: Mists of Pandaria
Game Element: Warlock Class Overhaul
Discipline: Class Design

(This is part 2 of a multiple-part series. You can read part 1 over here. )

Welcome back!

Today, we’ll continue on our journey to overhaul the Warlock class and how I introduced a novel resource system that is now used in many, many games.

Tighten your grips on your fel magic, and let’s continue with our journey of overhauling the Warlock class.

Let’s explore how I introduced a novel resource system that then got mass-adopted and became a cornerstone of many, many games.

Updates will be shared exclusively over at: https://gamedesignskills.com/funsmith-tavern/.

Chaotic Energy was created with a series of simple goal posts:

  • Can we create a caster class which turrets but isn’t stationary
  • Can we create a resource system that creates tension
  • Can we create a flow that feels like playing music

The latter point is one I want to reinforce.

If Affliction is about multi-tasking and juggling, then I wanted Destruction to be about consistency, focus and decision-making.

All qualities that reflect the experiences of a pianist.

And why not?

There’s very little difference in your physical motions and the habitually used buttons in WoW are even called rotations by the players.

Traditionally, WoW caster classes suffered from a problem known as ‘Input lock’ – you sit there constantly mashing a button to ensure that your attacks started up one after another as closely as possible, with little or no lost downtime.

This dramatically favored players with lower latency.

In late Burning Crusade, I worked with Sam Lantinga to develop a client-side queuing system for spells.

As a former addon developer, we had discovered it was possible to glitch out the client-side command processing system and insert your next spellcast sooner, increasing your damage and reducing the number of times you had to push a spellcasting button by pushing a macro.

Known as stopcasting macros, I’ll leave the technical details to the side for now – but suffice to say it didn’t break any game rules – but it DID change the physical feeling of playing a caster.

What was once ‘button mash as quickly as possible’ became ‘press the button at as precise a timing as possible’.

However, I’m an intuitive, idealistic rationalist – and while each of these experiences was interesting and unique – neither model is part of the physical or mental fantasy of playing World of Warcraft.

second to none
(This was the first thing that came up when I googled “chaotic Energy“)

Energy Goals

Ultimately, all of these little input details are barriers to immersing yourself thoroughly into the experience of Warcraft, which is a game of exploration and combat, framed by a beautiful pathway of small stories.

Both spamming a button and precisely hitting a button put the focus more on the physical execution of the game than on the tactical or strategic experience of the game itself.

For those of you who get confused like I do – tactical is small bits, like getting out of the fire, while strategic is utilizing your talents, items and abilities to achieve a broad objective.

Chaotic Energy was a new passive effect I added.

It increased mana regeneration by 625% (So your mana bar recharged fully every 20 seconds), modified the cost of all basic spells and removed Life Tap.

Chaotic Energy introduced an interesting and important dynamic – combining two principles very important to me as both a designer and a human being:  pressure and forgiveness.


Because chaotic energy would rapidly overflow your mana bar, excessive distraction or inability to fully utilize your energy pool was punished.

This provided a sense of urgency to be acting and casting.


Because chaotic energy regenerated at a steady rate, and the rate of expenditure was faster than the rate of regeneration, it was okay if you occasionally went a fraction of a second without casting.

This allowed small mistakes – and small tactical adjustments (such as moving out of the fire) to not heavily penalize your damage numbers.

Compare this with Life Tap.  If you are out of mana – you MUST be pressing Life Tap to keep optimal damage going.

If you take a break of any sort – you’re making a mistake.  This type of pressure is relentless, unforgiving and unnecessary.


The combination of Pressure and Forgiveness showed promise as a potential designer’s wet dream.

Both positive and negative reinforcement in the same system, guiding players to mix both internal (rotation) and external (situational) awareness – along with the breathing room to make the right decision – rather than simply focus on button mashing as fast as they possibly can.


I knew this system had immense potential. Possibly even the capability to become the baseline for the healthiest casting system in WoW – at least within the context of a dungeon or raid fight.

However, the first version of Chaotic Energy had a problem.

The Burning system worked like Combo Points on a rogue – Ember Tap or Chaos Bolt dumped all of your built-up power.

Then, you would sit there with nothing to do. Frantic build-up.  Massive release.  Emptiness.

What did this mean?

broc5bec3adk vc3a1clav hus pc599ed koncilem 6 c48dervence 1415
The Trail of Jan Hus at the Council of Constance by Vaclav Brozik, 1883

Consulting the Council

I turned to the council and shared this experiment with them.

I confessed that I hadn’t played a Rogue – and saw some awesome potential for using this – but why did this work there and not here.

Fortunately, one of the players was a highly analytical rogue player – and explained it quite clearly.

The rogue worked because you already have a constant filler action – moving and repositioning.

Trying to stay behind the target kept most rogues busy.

This wouldn’t work here, would it?

A quick test at adding a backstab bonus to Fel Flame confirmed that – positioning bonuses aren’t wise.

So what to do instead?

Another Warlock suggested a small change: what if it took longer to reach maximum charge – but you could spend your ‘Burning’ power in separate chunks.

It was like a lightbulb illuminated a dark room in my mind.

There was no need to replicate the rogue-like feel entirely: casters are not about commitment, caster classes are about decision-making.

Setting this as my new anchor point, I used buff stacks counting up to 40 to represent this new resource and decided to see what laid beyond.

Warlock AllWeAre
This is about what the WoW gender ratio felt like. (In truth it was much higher, but many women felt afraid to speak out due to mistreatment in game)

Burning Embers and the Music of Destruction

This pivot proved to be the turning point for the Warlock revamp.

Using a concept that I’ll call ‘Capacitance’ (like an electrical capacitor)  – I realized most Warcraft abilities had been locked into two camps.

Small time scale – things done within 5-10 seconds

Large time scale – things done once every 2-3 minutes or more

Regular rotation abilities fit into the former, while pets, cooldowns and so-on fit into the latter.

Now, the reader may proclaim -‘wait there’s totally  30 second cooldown abilities’ – and you’re right.

However, cooldown isn’t what this is about – its about the overall time-scale of decision making.

Think about it a bit more:

  • You have your super low or zero cooldown abilities that you spam
  • You have your cooldown abilities which replace what you would be spamming
  • You have your long cooldown abilities which you use at the ‘right moment’

While you can perform this dance better or worse, ultimately, you are performing the Designer’s dance.

Your ‘skill check’ is how well you can perform their ideal dance.  This really struck home when I saw the first AI controlled combat bots devastate the average damage of a player in WoW.

WoW was rewarding execution – not decision making.

So I set out to create a class that heavily encouraged strong decision making.

Enabling Decision Making

What are the criteria for decision making in a game like wow?

  1. There have to be different answers
  2. There have to be different situations where each answer is correct
  3. There has to be ambiguity to allow player choice to be relevant
  4. There has to be flexibility to choose when and how to provide your answer

Looking at mechanics in the pre-MoP Warlock era – 1 and 2 definitely existed.

You kick or spell lock a spell and you shadowburn a low health target.   3 exists just by nature of the sheer complexity of the WoW experience.

No two raid fights are exactly alike, just like no two attempts are exactly alike either.

So the missing factor had to be #4:  a lack of flexibility.

My favorite example of this missing principle is the Rogue combo point system.

Rogues have some valid choices with their combo points – burst damage, attack speed, etc.

However, they don’t have much of a choice on WHEN to use those skills.

Either they push the button before their energy bar fills up – or they wasted some combat potential.

However, the rogue points at the right solution – what if, instead of capping out at five, you could spend up to five combo points – and have a cap of much, much more?

This was where I went with the Warlock.


The Capacitor Class

While I framed it like a new idea, in truth the Warlock had been a capacitor class from the start.

Soul Shards, which were harvested from a short skill test (Drain Soul) unlocked more powerful and unique abilities for Warlocks as far back as WoW Alpha.

Summoning other players, casting a super high damage nuke (Soul Fire) and allowing you to resummon a pet were all things you could do only a limited number of times unless you passed the Soul Shard skill check – or had extras built up earlier.

It made sense to make this a core mechanic of the class.

So I expanded this concept – particular in destruction – by giving Conflagrate two charges.

This allowed the destruction warlock to wait a few seconds before using their conflagrate – or let it pool completely to burst two conflagrate spells back to back later.

It worked.

There was now clean rotation to Destruction.  Immolate, Conflagrate, Incinerate X times, Repeat once, Chaos Bolt… or save Chaos Bolt for later.

The best part?

It didn’t change the overall DPS of the class, unless the Warlock player took advantage of situational bonuses (monster vulnerabilities or self-triggered proc effects) – but that was exactly the kind of self-defined skill I wanted destruction to reward.

Again, let me reinforce this incredibly important point:  Twin charges and Burning embers put the control of WHEN to push buttons back in the hands of the Warlock player, not the designer.

UI & Support

In a previous expansion, the Warlock Soul Shard inventory management game (which was never fun anyways) had been removed and replaced with a 3-shard UI element.

It made sense to upgrade this element to support the new gameplay mechanic.

While I could simply recolor the mana bar and make it fill faster for Chaotic Energy, it didn’t make sense for soul shards to simply ‘pop’ into existence after pressing. Incinerate several times.

I dropped by Kyle’s office and asked him how much work it would be to support 1/10th of shards, instead of only whole shards.

Kyle: “Supporting it in code is easy. We’ll just multiply the values by 10. However, the UI work is much, much harder to do?”

Alex: “Because creating UI is hard? I could probably help code it up if necessary.”

Kyle: “No…. because the UI artist is thoroughly slammed.”

I went to speak with the UI and Gameplay Programming leads (who happened to share an office).

Pat: “What’s this I’ve been hearing about a class rebuild?”

Alex: “Warlocks have been in shabby shape for a long time.

We are taking the risk of making a lot of changes in one expansion to overhaul them completely – and see if it brings new life to the class.”

Pat: “Well, the other class designers are still figuring out what features they need for this expansion.

If you can bring us a complete list of everything you want to do soon, we’ll get it done.”

UI Lead (I’m sorry, I forgot your name T_T):  “The UI Team is pretty slammed… but if you can get a list of what custom resources you want, we’ll figure it out.

The only catch is – we need to know *all* of the changes at once – we aren’t going to have time to go back and add more later.”

Pat: “Just get Ghostcrawler to sign off on the list of what you need and we’ll get it done.”

Alex: “Well…. then I guess I need to figure out Demonology first.”


In my quest to improve the gaming experience for the “affliction” warlocks, I recognized the burden of incessantly spamming keys and diligently endeavored to reduce this pressure load.

However, my efforts resulted in extensive changes that, despite being loved by players, sparked a backlash from the lead developer a few days before launch.

This experience taught me a valuable lesson: implementing significant changes can be daunting and met with uphill resistance.

It highlighted the importance of having allies and advocates who share your vision and can help navigate the challenges to ultimately bring these bold and transformative ideas to fruition.

Continued next time…

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23 Responses

  1. Thanks for writing these posts on the development of warlock. I started playing near the end of Mists of Pandaria and warlock has always been my favorite class. I want to thank you for your work on something that has provided me countless hours of enjoyment. Looking forward to the next post 🙂

    1. You are welcome. Many people (Over 100!) Worked on Mists and supported the work that the design team was able to achieve.

  2. Interesting read. Admittedly, destro was always the least interesting tree to me. I figured if I wanted to blow something up I’d play a mage, however back in vanilla I learned that destrolocks gained the nickname of ‘suicide mages’. The were commonly understood as the quintessential glass canons, giving up pretty much all forms of defense for the sheer nuking capability.

    They could melt you in 1 or 2 hits, but could be melted with equal ease. 😉

    Locks had no aggro dump then, either. Destro was intended to be a dangerous spec. The threat of drawing boss aggro was effectively the throttle for the destrolock then, but this effectively put control of your damage output in the hands of the skill and gear of your tank.

    I remember destrolocks popping ppl in pvp was very problematic, as well as the discontent of no reliable aggro drop and thus relying on your tank to functionally dictate your damage output. I can see the need for the changes over the years, however the charm of the ‘dangerous caster’ ended up getting wiped away with it.

    The idea of storing Chaotic Energies that could rip you apart struck me as a good effort in bringing this fantasy back to destro. It was my least played spec, but I could see how the idea of a suicide mage could pronounce the difference from a regular, normie mage.

    1. That was my idea too. Ultimately, we had to remove the damage – something I didn’t go over in the post – because it didn’t play well in group content.

  3. I’ve played destro since forever and only with legion switched to a mage. The class started to feel slower than usual and on top of that the talent changes drove me away. I was used to having control spells for every occasion that combo together. But now I have to choose between my favorite spell shadowfury, death coil and portal.

  4. Thanks! Also it would be interesting to hear some thoughts about warlock’s state in Draenor-Legion-upcoming BfA

  5. Man, you were the best. You knew us, understood us.

    I’m playing Warlock from a long time, and i so much miss MoP iteration of the class.

    It is true, it wasn’t perfect, but faaar better than Legion iteration.

    Thank you for your work back then, thank you for those good memories with my Destro lock!

  6. Love the insight into the design progress of such a major (and successful) rework. However, not only the design aspect makes this post intriguing, I think the impact this challenge had on you as a designer is also highly interesting.

    Looking forward to reading the next blog post

  7. I detest what happened to affliction with the revamp, but it’s enjoyable reading the destruction process.
    MOP destruction was fantastically designed. Very interesting to read how you came to emberbits and makes me all the more baffled as to why Blizzard moved away from them briefly in WOD, it worked so well.

  8. Xelnath, I just want to say thank you.

    I have been a lock for 12 years (give or take) and have mained destro since MoP. I am one of the few dest locks I see running around (have yet to encounter one who can beat me :P, Aff is a crapshoot) and it is because of you and your insight to what makes a warlock a warlock the reason I love this class so much. Expansions come and go and people change mains but I have and will always be a destruction warlock. There’s something innate about being the bringer of chaos and doom that brings me utter satisfaction. Whether it’s havocing 2 mobs for 5m chaos bolts apiece or bringing down [green] fire from the sky. Destruction has always been my favorite spec, the way you realized some folks wanted to be petless not just for the crappy pet UI but because as a warlock we will do anything to see our enemies burn – so much so we will sacrifice ourselves and our pets.

    I hope for the day we can be back to that mindset and playstyle. Your vision, while maybe not a core part of the current developers, has not been lost on those who truly know what it means to be a warlock and what it takes to be destruction. Keep on riding man!! This was an AMAZING read.

    1. Thank you. I feel like Destruction had the clearest purpose in my own mind in MoP = and it showed in the result.

      Affliction was painful because it was tearing off a lot of bandaids. The results though have lasted for quite a while – Shard driven stacking DoTs, channel and lifesteal focus, etc. So that’s enjoyable to see. Demonology … well, that’s a whole blog article.

  9. The stacking dot mania of affliction is something I will never understand. Despite explicit statements over the past several years (back in WoD and even MoP a bit already) about how the game evolved away from ramp more towards burst, how can developers still stick to this archaic system.

    It’s not a “skill cap” anyway because a toddler can count to 10…

    In any case, I wanted to say THANK YOU for this amazing read. Not only because of the content but also because the way you write is absolutely beautiful. Keep up the good work, can’t wait for part 3!

  10. Something that was very prevalent in the warlock design of MoP which was increadibly satisfying was the room for decision making. Soulburn played a big part of that, espexially inn pvp (empowering utility spells in return for a soulshard cost). But your design had that even for dmg. Demonology could pick almost any time to metamorph in return for staying in it for a shorter duration. Destruction could burn an ember for healing, and like the article note could hold on to casting for some moments when they had to move. The ability to make meaningful choices with your resources and time, for both damage and utility gains, was a masterpiece. Thanks for that.

  11. Really enjoying it, I’ve always had curiosity for this story, and WoD demonology was the best spec I ever played (didn’t have the pleasure to play MoP). I mean for real Demo WoD was hard and rewarding, it was amazing… I would give so much to have it back…

    Also, the waiting for part 3 it’s being too long, moaaaaar please!!

  12. Really enjoying it, I’ve always had curiosity for this story, and WoD demonology was the best spec I ever played (didn’t have the pleasure to play MoP). I mean for real Demo WoD was hard and rewarding, it was amazing… I would give so much to have it back…

    Also, the waiting for part 3 it’s being too long, moaaaaar please!!

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