This short article looks at the Arcane Mage rotation. Specifically, it examines the idea of the “Burn Phase” or the rotation in which you spend mana without care vs. a “Conserve Phase” where you dump Arcane Charges frequently with Arcane Barrage.
Before I dive into the rotation, I always start rotation analysis articles with this statement/reminder that is core to my approach to rotation development:
Optimal DPS is rarely determined by a player’s ability to perform complex rotation logic - it is most often determined by their ability to Always Be Casting (ABC).
Keeping this in mind, I try to factor rotations down to the simplest set of rules possible that can be used for optimal DPS, which allows more focus to be spent on fight mechanics.
In general, the way that Arcane Mage rotations are thought about is the following:
1.) Burn Phase: When you can use Evocation or will be able to use it soon, you burn your mana and use your big cooldowns like Arcane Power and Rune of Power.
2.) Conserve Phase: When you are waiting for Evocation to be ready, you use Arcane Barrage to dump Arcane Charges whenever you get to 4 charges and cannot take a mana-neutral action or keep your mana high.
This then leads to the question: When do I start burning my mana? How long do my burns usually last? Should I start with 30 seconds left on Evocation’s cooldown? More? Less?
When we created our simulator for Legion, we introduced this feature called “Learned Variables” that is especially suited to figuring this problem out. We add a “switch” to the rotation that turns on when you start the Burn Phase and then turns off when you cast Evocation and end the Burn Phase. The simulator keeps track of the duration on every iteration and then learns the average value. This can then be used to predict when you should begin burning mana.
The assumption here is that you want to run out of mana in close proximity to when the cooldown of Evocation is ready. Another assumption is that using Evocation as many times as possible in a fight is always optimal.
I was creating a “simple” Arcane rotation for the purpose of doing some benchmark tests that would compare the AMR simulator and SimC in order to identify any possible bugs. For this simple rotation, I purposefully took out any logic that depended on tracking the length of Burn Phases. I also stripped out the concept of a burn/conserve phase distinction. My expectation was that I would lose significant damage, but, it wouldn’t matter for benchmark testing aimed at locating bugs.
But, something unexpected happened… the “simple” rotation does just as much damage as the traditional rotation. It does this without ever caring or knowing how long a “Burn Phase” lasts. It does this without even having the concept of a “burn phase” and “conserve phase” explicitly defined.
The “Simple” rotation follows these basic rules to achieve optimal DPS:
1.) Use Arcane Power on cooldown as long as you are at max Arcane Charges.
2.) Use your other cooldowns (Rune of Power, Trinkets, Racials, Potion, etc) with Arcane Power.
3.) Do not dump Arcane Charges if you have Arcane Power up, Rune of Power up, or if you can use Evocation right now.
4.) Use Evocation only when you cannot cast any other spell.
5.) Dump Arcane Charges with Arcane Barrage if the conditions in rule 3 are not met.
The only other rules in the rotation are around making use of Presence of Mind and Charged Up.
For Charged Up:
1.) Prioritize using Arcane Barrage if Charged Up is available.
2.) Use Charged Up right after Arcane Barrage.
For Presence of Mind:
1a.) Without 2T20, use when you have Arcane Power or Rune of Power and there are less than 3 targets in range of Arcane Explosion.
1b.) With 2T20, instead you will use Arcane Barrage first thing after using Arcane Power, followed immediately by Presence of Mind. Don’t use Presence of Mind at another other time.
These simple rules end up with a single-target rotation that looks like this:
1.) Mark of Aluneth if Arcane Power is ready or you have less than 85% mana
2.) Rune of Power if Arcane Power is ready and you are at max Arcane Charges, or if you have Arcane Power up
3.) Arcane Power at max Arcane Charges
4.) Use Potion, Racials, Trinkets with Arcane Power
5.) Arcane Barrage, Presence of Mind if you have 2T20 and Arcane Power
6.) Arcane Barrage, Charged Up (if you don’t already have T21 2pc buff up)
7.) Arcane Missiles
8.) Presence of Mind if you don’t have 2T20 and have Arcane Power or Rune of Power and can’t AoE
9.) Arcane Blast if you have Arcane Power, Rune of Power, or can use Evocation
10.) Arcane Barrage if you have max Arcane Charges
11.) Evocation (usually interrupt before the last tick, since it is unnecessary)
12.) Arcane Blast
For AoE, just replace Arcane Blast with Arcane Explosion.
And… that’s it! This rotation results in optimal DPS. You burn mana whenever Arcane Power is up, and whenever you can use Evocation. You don’t have to worry about how long your burn phases may or may not last. You don’t have to time up the start of a burn with Evocation’s cooldown. You don’t need to worry about using Rune of Power in between burn phases. You don’t need any logic for saving Charged Up for a burn phase.
I will provide a few spot tests that I did. The AMR Default rotation uses the traditional burn/conserve setup.
Where I saw the biggest differences in spell use between the traditional rotation and this new simplified rotation was when I try builds with Mystic Kilt of the Rune Master. Traditionally, we have been trying to maximize the uses of Evocation in a fight, since that seems like it would lead to maximum DPS. This rotation makes no attempt to maximize Evocation use. Here is an example of a player in very high item level gear using Mystic Kilt of the Rune Master:
We see a 0.5% difference in DPS between the Simple Rotation and the more complicated traditional rotation. The big difference here is that the Simple Rotation only uses Evocation 2.1 times, while the traditional one uses it 3.2 times. Maximizing Evocation use through tracking of average burn duration is yielding no noticeable DPS gain.
I added a protection into the Simple Rotation that forces a cast of Evocation before Arcane Power comes off cooldown if mana is starting to get low, since you can cast spells almost indefinitely with the Kilt using the 4x Arcane Blast, Missiles, Barrage rotation. Once in a while that would result in running out of mana while Rune of Power is up, which we certainly don’t want to happen. It has a very small impact on DPS, but, it is something that players would invariably want to do in-game because running out of mana with Rune of Power up feels bad.
So, that is one extra simple rule: If Arcane Power is going to be ready soon, cast Evocation if it is available and your mana is below 40% or so.
Here is an example of a player with the favored item setup at the time of this post: Shard/Soul rings and 2T20 + 4T21:
Simple and AMR Default give identical DPS results. Once again, the Simple Rotation gets us a surprisingly good result.
The big difference that a player would notice in-game using the Simple Rotation is that we are used to casting Evocation while at max Arcane Charges and then entering into a conservative rotation. This new rotation will dump the Arcane Charges before using Evocation and then continue to build up charges until we simply cannot cast a spell anymore, then use Evocation. This is why the builds with Mystic Kilt end up using Evocation so much less frequently: The mana gain from Arcane Barrage and regen while using Arcane Missiles often lets you build up to 4 charges again before you run out of mana.
This seems like a bad idea… riding at really low mana when you could just use evocation? Apparently it doesn’t matter as much as we thought!
I ran a comprehensive set of benchmarks comparing this rotation to the traditional rotation, and there is no case where the traditional rotation is 2% or more higher. In the vast majority of cases the two rotations are within 1% DPS of each other.
In practice, the rotations do very similar things. The main boon of the Simple Rotation is that we don’t have to worry about the idea of burn/conserve “phases”. Use mana when Arcane Power/Rune of Power is up and when Evocation is ready. That is very easy to remember and perform, and it has no dependence on how many Arcane Missile procs we get.