Going Arcane, Part 2 - Therorycrafting Basics
by Tachyon on Wed. 18. February 2009, 00:57
Filed under: arcane, spec, raiding, dps, patch, theorycrafting
- Arcane Blast, Arcane Missiles and Arcane Barrage for single-target damage
- PoM-Flamestrike and Blizzard for AoE (Area of Effect) damage
A good arcane talent spec that gets the optimum out the damage capabilities will put 3 points in fire (for Incineration, as it affects Arcane Blast), at least 11 points in frost to get Icy Veins and the rest in the arcane tree.
Personally I prefer to have 12 points in frost for more AoE damage (3/3 Ice Shards), so my recommended spec is something like this:
56/3/12 Arcane Raid Spec.
Some mages recommend more pushback protection by adding 3-4 points into Arcane Stability, but it's really hard to ditch some points there as it usually hurts other good talents.
Manly from Elitist Jerks even suggests a spec without Slow, and he's right for raiding as you really don't need the talent there, but boy I wouldn't run around without it outside a raid instance, so I'd rather sacrifice that points elsewhere, if at all.
I won't go into details for AoE damage in this article, as with the rotation above (and preferrable Arcane Power), it's straightforward to do massive(!) damage to multiple targets. So let's focus on the single target spells instead.
8% of base mana (261 Mana at lvl 80), 30 yd range, 2.5 sec cast
Blasts the target with energy, dealing 1185 to 1377 Arcane damage. Each time you cast Arcane Blast, the damage of all Arcane spells is increased by 15% and mana cost of Arcane Blast is increased by 200%. Effect stacks up to 3 times and lasts 10 sec or until any Arcane damage spell except Arcane Blast is cast.
Glyph of Arcane Blast: Increases the damage from your Arcane Blast buff by 3%. This makes the arcane blast debuff increase the damage by 3% per stack, so it's +18%, +36% and +54% for 1-3 stacks. That glyph is really recommended.
Spell Power Coefficient: 2.5/3.5+0.09 = 80.429%
The coefficient is scaled to the cast time (2.5sec), plus gets 9% from Arcane Empowerment (3/3).
Crit Multiplier (with 4xT7 + CSD): 1+(((1.5*1.03)-1)*(1+0.5+0.05)) = 1.84475
This includes the CSD meta gem (3%), the Spell Power talent (50%), the 4xT7 set bonus (5%). Without the 4xT7 bonus, it would be 1.8175, so it's not much of a difference. The CSD ( Chaotic Skyflare Diamond or Chaotic Skyfire Diamond) however is not negotiable, you're just expected to have it, no way round!
31% of base mana (1013 Mana at lvl 80), 30 yd range, Channeled (5 bolts in 5 sec)
Launches Arcane Missiles at the enemy, causing 360-361 Arcane damage every 1 sec for 5 sec.
Spell Power Coefficient: 5/3.5+0.45 = 187.857%
The coefficient is scaled to the full channel time (5sec), plus gets 45% from Arcane Empowerment (3/3).
Crit Multiplier (with 4xT7 + CSD): 1+(((1.5*(1+0.03))-1)*(1+0.5+0.05+0.25)) = 1.981
This includes the CSD meta gem (3%), the Spell Power talent (50%), the 4xT7 set bonus (5%) and the Glyph of Arcane Missiles (25%). Without the glyph, the coefficient would be 1.84475, so the glyph increases your AM crits by 7.39%
Arcane Missiles become really nice when used on a Missile Barrage proc (20% proc chance after using Arcane Blast or Arcane Barrage), reducing the cast time by 2.5sec and thus doubling the DPS for that spell.
18% of base mana (588 at lvl 80), 30 yd range, Instant cast, 3 sec cooldown
Launches several missiles at the enemy target, causing 936 to 1144 Arcane damage.
Spell Power Coefficient: 2.5/3.5 = 71.429%
This may not seem high, but take into account that this is an instant cast spell. The usual coefficient for instant cast spells will be weighted by the global cooldown time in place of the cast time, so it should be 1.5/3.5 = 42.857%. That's a significant boost, so this spell will scale extremely well with spell damage (66.7% more than compareable spells such as Fire Blast).
Crit Multiplier (with 4xT7 + CSD): 1+(((1.5*1.03)-1)*(1+0.5+0.05)) = 1.84475
This includes the CSD meta gem (3%), the Spell Power (2/2) talent (50%), the 4xT7 set bonus (5%).
Theorycrafting Scenario
For the following scenario, we consider a 57/3/11 standard raid spec with 2000 spell power, 35% crit and 10% haste, hit capped (100%).
Basically we could leave out the haste as well as all talents (Spell Power etc.) or raid buffs/auras that scale the DPS proportionally, as it affects all rotations equally, and your mileage may vary anyway. For comparing the spells and rotations, that scenario suffices well, and if you need exact numbers, just replace the numbers above with whatever works better for your.
Time to start the number crunching!
The average base damage for a spell will be:
avgBaseDmg:= (minDamage+maxDamage)/2The effective cast time for a spell is the base cast time (or GCD for instant cast spells) divided by the speed multiplier from haste (1+haste). The GCD (Global Cooldown) is also affected by haste, but won't go below 1 sec. For our scenario, we take the 10% haste plus the 6% from talents (Netherwind Presence).
castTime := baseCastTime / (1 + haste)The average damage is the base damage plus the spellpower times the coefficient, times any talents that multiply the damage (3% from Arcane Instability, +6% for ArcaneBlast with Spell Impact, and 12% in a raid scenario from Torment the Weak)
dmg(hit):= (avgBaseDmg + (spellpower * coefficient)) * multiplierFor the mana costs, we consider -3% from Arcane Focus, and -3% from Precision, but for the time being ignore any Arcane Concentration procs (just substract 10% from the average mana/sec in the end).
Here's what we get so far:
| . | Arcane Blast | Arcane Barrage | Arcane Missiles | Missile Barrage |
| Dmg Avg | 1358 | 1040 | 1807.5 | 1807.5 |
| Mana | 261 | 588 | 1013 | 1013 |
| Mana /w talents | 245.34 | 552.72 | 952.22 | 952.22 |
| Cast Time | 2.50 | 1.50 | 5.00 | 2.50 |
| Cast Time /w haste | 2.155 | 1.293 | 4.31 | 2.155 |
| Coefficient /w talents | 80.429% | 71.429% | 187.857% | 187.857% |
| Dmg Avg | 2966.57 | 2468.57 | 5564.64 | 5564.64 |
| Dmg Avg /w talents | 3233.56 | 2542.63 | 5731.58 | 5731.58 |
| +Torment the Weak | 3621.59 | 2847.74 | 6419.37 | 6419.37 |
The average critical damage per spell is just the average damage, multiplied by the crit factor (Arcane Blast gets an extra 6% crit from Incineration):
dmg(crit):= dmg(hit) * critMultiplier| . | Arcane Blast | Arcane Barrage | Arcane Missiles | Missile Barrage |
| Crit Multiplier | 1.84475 | 1.84475 | 1.981 | 1.981 |
| Crit Dmg | 6680.93 | 5253.38 | 12716.78 | 12716.78 |
To find out the average damage, including crits, we'll have to weight that outcomes by the hit, crit and miss probabilities.
p(crit) := critChance * (1 - p(miss))
p(hit) := (1-critChance) * (1 - p(miss))This leads us to the average damage numbers for our scenario. Divide those by the cast time and you get the DPS, or divide it by the mana cost to get the DPM.
| . | Arcane Blast | Arcane Barrage | Arcane Missiles | Missile Barrage |
| Avg Dmg | 4967.70 | 3761.88 | 8812.39 | 8812.39 |
| DPS | 2305.01 | 2909.19 | 2044.47 | 4088.95 |
| DPM | 20.25 | 6.81 | 9.25 | 9.25 |
So far so good, we got the basic numbers we need to calculate our spell rotations in Part 3 of this series.