WotLK: What Spell Do I Use? - Spell Rotations

This is the second part in a three part series looking at what spells moonkin should use for WotLK Raiding. Part one looked at the basic math of our four main DPS spells. Part two looks at what spell rotations moonkin should use and wen. Part three on Eclipse is cancelled for now.

UPDATE: The numbers have been updated to include the new base spell values. The TL;DR version did change a little bit as the Starfire Rotation improved significantly.

Knowing the basic math behind each spell is nice and all but it doesn't give the whole picture. These spells are interrelated and preform best when used in conjunction with each other.

In this post I will look at four different spell rotations. I will review which are best in some situations, and which should be completely ignored.

If you don't care about all of the math or assumptions please feel free to skip to the bottom for the TL;DR version.

Assumptions:
1. All of my math is based upon the calculations I did in my DPS Basics post. Therefore, the same assumptions hold true.

2. Just to reiterate, I am excluding the Glyph of Wrath, because spell push back is hard to quantify. This is biased against Wrath, but I will try and acknowledge the issue in my conclusions.

3. I won't be using Starfire and Wrath in the same rotation. In the past some oave argued that Wrath you be the last spell in your rotation if you have less then 1.5 seconds left on your DoT. While this is technically true, I believe it complicates the rotation to an unreasonable level. Overly complicated rotations can lead to decreased DPS because of mistakes made in trying to execute them. Therefore, I will not be using this practice in my rotations listed below.

4. Moonfire and Starfire are assumed to be glyphed, but Insect Swarm is assumed not to be. There is no downside to the Moonfire glyph, and the Insect Swarm glyph only improves my conclusions and a rotations DPS if included.

5. The additional Moonfire damage from the Starfire Glyph will be attributed to the Starfire cast and not Moonfire.

6. All rotations are created using average cast times. These numbers can very significantly depending on the number of crits that occur and proc Nature's Grace.

Talent Build / Buffs:
I am using the same build to calculate these rotations as I used in the DPS Basics post. Please refer to it for specifics. However, I would like to highlight one additional talent.

Improved Insect Swarm - Increases the damage of your nuke spells based upon the DoTs on the target.
Nature's Splendor - Increases the duration of your Moonfire and Insect Swarm spells by 3 sec.

Creating a Spell Rotation:
Spell Rotations are defined by two charicteristics: DoTs and Cooldowns. Without DoTs or Cooldowns, we would just pick our best spell and spam it.

Moonkin don't have a "standard" long cooldown spells. Yes, you could include Starfall or Force of Nature, but realisticly they are not going to be included in any standard rotation. So, Moonkin rotations are going to be centered around our two DoTs: Moonfire and Insect Swarm.

With Nature's Splendor Moonfire and Insect Swarm have a duration of 15 seconds. Therefore all but one of the rotations will be centered around this 15 second DoT timer.

The rotation depend on how many "nukes" you can fit in the duration of the DoT(s). To do this we need to determine the average cast time of Starfire and Wrath and the average global cooldown for Insect Swarm and Moonfire.

Cast Times / Global Cooldowns:
As I said we in the assumpions, I am using the same stats as the Basic's post. That means my hypothetical moonkin has 11.31% haste, Starfire and Wrath have 30% crit, and Moonfire has 36% crit. Here is how you calculate each spell's cast time or global cooldown.

Starfire w/ Imp IS: (3 - (0.5 * (Crit + 0.03)))/ (1 + haste) = (3 - (0.5 * 0.33)) / (1 + 0.1131) = 2.5469 seconds

Wrath: (1.5 / (1 + haste))*(1 - Crit) + Crit = (1.5 / (1 + 0.1131))*(1 - 0.3) + 0.3 = 1.2433 seconds

Moonfire: (1.5 / (1 + haste))*(1 - Crit) + Crit = (1.5 / (1 + 0.1131))*(1 - 0.36) + 0.36 = 1.2225 seconds

Insect Swarm: (1.5 / 1 + haste) = 1.3476 Seconds

Improved Insect Swarm:
I didn't include this talent in my basics analysis because it is a very rotation dependent talent. However, it does have a significant impact on spell DPS. Here is how the equations are modified for this talent.

Wrath:

DPS = (((Base + (Spell Power * 0.67))*(1 + (0.32 + Imp IS)))*(1 + Crit)) / ((1.5/(1+Haste))*(1 - Crit) + Crit)
DPS = (((588 + (1800 * 0.67))*(1 + 0.32 + 0.03)))*(1 + 0.3)) / ((1.5/(1+0.1131))*(1 - 0.30) + 0.30)
DPS = (1,794* 1.35)*1.3 / (1.3476*0.7) + 0.3
DPS = 3,148 / 1.2433 = 2,532.25

Starfire:

DPS = (((Base + (Spell Power * 1.2))*(1 + 0.32))*(1 + (Crit + 0.03)) / ((3-(0.5 * (Crit + 0.03)))/(1+Haste))
DPS = (((1120 + (1800 * 1.2))*(1 + 0.32)))*(1 + 0.33)) / ((3 - (0.5 * 0.33))/ (1 + 0.1131))
DPS = (4330*1.33) / 2.5469 = 2,260.93

Glyphed DPS = Starfire DPS + (Moonfire Tick / 3)
Glyphed DPS = 2,260.93 + (1,119/ 3) = 2,633.93

Spell Rotations:
The different rotations fall into two catagories: Starfire rotations and Wrath rotations. First, I'm going to compare the Starfire rotations and the Wrath rotations to find out which is the best Starfire rotation and which is the best Wrath rotation. Then, I am going to compare the Starfire and Wrath rotation to each other to find out which is best.

Starfire Rotations:
For these rotations I am assuming that Moonfire is already on the target. Therefore, I am ignoring the direct damage portion of the spell and the mana costs of the spell. This of course won't be true for all fights, but it should impact both rotations equally. Therefore, it should impact the analysis for now.

Moonfire, Starfire * X:
If Moonfire is already on the boss this is basically Starfire spam and therefore has the same DPS as shown above. So for my hypothetical moonkin this rotation has an average DPS of 2,633.98, and and averate DPM of 15.80.

Moonfire, Insect Swarm, Starfire * X:
The main question here is how many Starfire's can we cast while Insect Swarm ticks on the boss. Insect Swarm has a duration of 15 seconds talented and a GCD of 1.3476.

SF casts per IS: (15 - 1.3476) / 2.5469 = 5.36; rounded up to 6

So this means that on average our rotation will consist of 1 Insect Swarm cast and 6 Starfire casts. This results in a rotation DPS of :

Rotation DPS = (IS Dam + (SF Dam * 6)) / (IS GCD + (SF Cast Time * 6))
Rotation DPS = (4,220+ (6878 * 6)) / ( 1.3476 + (2.5469* 6))
Rotation DPS = 45,485 / 16.629 = 2,735.28

Rotation DPM = 45,485 / (304 + (435 * 6)) = 15.61

At a 30% crit rate the IS, MF, SF rotation does about 3.85% more DPS but is only 1.28% less mana efficent then the MF, SF rotation. Therefore, it is my suggestion that an IS, MF, SF*x rotation be your primary Starfire rotation in early raiding.

Wrath Rotations:

Insect Swarm, Wrath * X:
How many Wraths can we cast while Insect Swarm ticks on the boss. Insect Swarm has a duration of 15 seconds talented and a GCD of 1.3476.

Wrath casts per IS: (15 - 1.3476) / 1.2433 = 10.98; rounded up to 11

So this means that on average our rotation will consist of 1 Insect Swarm cast, 10 Wrath casts with Imp IS, and 1 Wrath cast without Imp IS. This results in a rotation DPS of :

Rotation DPS = (IS Dam + W Dam + (W IS Dam * 10)) / (IS GCD + (W Cast Time * 11))
Rotation DPS = (4,220 + 3,083 + (3,153 * 10)) / ( 1.3476 + (1.2433* 11))
Rotation DPS = 38,833/ 15.0239 = 2,584.74

Rotation DPM = 38,833/ (304 + (273 * 11)) = 11.74

Moonfire, Insect Swarm, Wrath * X:
How many Wraths can we cast while Insect Swarm and Moonfire ticks on the boss. Both DoTs hav a duration of 15 seconds talented. Insect Swarm's GCD is 1.3476, while Moonfire has an average GCD of 1.2225.
Wrath casts per Rotation: (15 - 1.3476 - 1.2225) / 1.2433 = 9.99; rounded up to 10

So this means that on average our rotation will consist of 1 Insect Swarm cast, 1 Moonfire cast, 9 Wrath casts with Imp IS, and 1 Wrath cast without Imp IS. This results in a rotation DPS of :

Rotation DPS = (MF Dam + IS Dam + W Dam + (W IS Dam * 9)) / (MF GCD + IS GCD + (W Cast Time * 10))
Rotation DPS = (5,733 + 4,220 + 3,083 + (3,153 * 9)) / ( 1.2225 + 1.3476 + (1.2433* 10))
Rotation DPS = 41,413 / 15.0031 = 2,760.30

Rotation DPM = 41,413 / (304 + 597 + (273 * 10)) = 11.41

The Wrath rotations are fairly even. The the IS, MF, W rotation has a 3.73% DPS advantage, but the IS, W rotation has a 5.96% DPM advantage. Which you choose will depend on your current needs, but if you need more mana efficiency then your probably not going to use a Wrath rotation. Therefore, it is my suggestion that an IS, MF, W*x rotation be your primary Wrath rotation in early raiding.

Starfire Rotation vs Wrath Rotation:
Which rotation is better really depends on the fight. The Starfire rotation is clearly better in terms of both DPS and DPM. However, this only holds true if you can keep appling Moonfire ticks with each Starfire cast and there is limited spell pushback.

The Starfire Rotation is best for long "tank and spank" type fights that have limited aggro dumps and limited movement. This rotation shine's when you can sustain consistant and focused DPS. The perfect fight for this rotation is one like Tidewalker, where you can sit there and build up as many ticks as possible with out worring about pulling aggro after a threat wipe.

A Wrath Rotation is best for the more highly variable fights like Leo. The Wrath rotation shines when you have to start and stop DPS frequently because it doesn't require the synergy between glyphs to provide good DPS. Also, a Wrath rotation is more predictable because you manage when your DoTs end to help you avoid pulling aggro. If you used a Starfire rotation in this situation you would lose a good chunk of the mana efficency because you have to reapply Moonfire frequently.

Ultimately you want to maximize your use of the Starfire rotation without pulling aggro or endangering the raid. There are plenty of situations where one rotation might be good for one phase but bad for the second.

Take Supremus for example. Phase one is great for Starfire, because you can build up Moonfire ticks to DPS during the Kite phase. Wrath is better for phase two because of the shorter cast time and you don't want to extend the Moonfire DoT into the aggro dump.

You can also use more then one rotation in a single phase. Take phase two of the Leo fight in SSC. You have a minute while he is in demon form. You could build up your Moonfire duration using your Starfire rotation until the duration of Moonfire is a little less then the time left in the phase. Then you switch over to your Wrath rotation to let the moonfire tick off.

TL;DR Version:
This is a lot of math and words so I want to summarize it into a more digestable format.

MF, IS, SF*x Rotation
Good: The Best rotation when managable. Great for long "tank and spank" fights that allow for continous and focused DPS.
Bad: For choppy fights with frequent aggro dumps that require you to frequently reapply Moonfire.

MF, IS, W*x Rotation
Good: For choppy fights that require greater control over your personal DPS.
Bad: For long consistent fights that require a greater level of mana efficnecy.