TLDR; simple fix - make runic diversity increase the damage of your 4th cast after successfully casting 3 different types of spells, & possibly increase the damage number to like +25% or 30%. OR make runic diversity also increase affliction dot damage.
Mage bread and butter: Fireball.
Fireball -> Frost -> Affliction is the most sensible combo.
- What gets the 20% damage increase? Affliction initial damage.
- Does the dot damage of affliction increase from runic diversity? No.
Your rotation would look like:
Fire->Frost->Affliction->Fire
- lose damage casting frost (2/3 fireball dmg)
- lose damage casting affliction (or break even roughly)
- lose damage by losing 1x buff “next spell does increased damage” by casting frost for frost affinity buff instead of fire affinity (13.6% per @Asmund_T)
- lose damage by boosting frost by 13.6% instead of fireball by 13.6% (from affinity fireball)
- lose damage momentarily via typical tileset buffs due to interference
- gain 20% damage to initial affliction impact (comparatively, this is 6.4% vs just casting fire & getting the 13.6% buff)
- gain 5% damage buff (up to 10%)
- gain 5% damage buff from iceheart
- gain 2 ticks of affliction that probably won’t have the chance to actually deal damage before being replaced.
Just think about the fire buff alone…
You lose 33% damage of a fireball casting frost(big), you gain 13.6% damage towards your next affliction(low). Rephrasing…runic diversity is giving you a 6.4% damage increase on your affliction over fireball by costing frost, but costing you a whopping 33% of a fireball. You do get 2 more ticks of affliction, assuming they live out their full lifespan, and that will be worth maybe 40% of a fireball (guessing off numbers). Because you need to maintain two stacks of that 5% damage debuff twice though, it will be unlikely.
So there’s no reason to use frost unless you have frostheart, and a rotation without frostheart actually looks like:
Fire->Affliction->Fire
For a change, frost w/ affinity could increase the duration of the true affinity affliction 5% dmg debuff, but it doesn’t. If it did, it would give you 2 more seconds to cast fireballs instead of affliction. What you actually get from affliction is 5% damage increase from affinity and you can only have 2 stacks of it, the real reason for casting affliction. Frost does nothing to support this 10% damage increase. It does instead however contribute to iceheart, the only reason to use frost in the rotation.
A decent runic diversity rotation would give everyone reason to use frost in their rotation, regardless of iceheart or not. A 20% damage increase is also quite low since you are already losing so much raw damage from casting frost & affliction. Something like +30% would be more appropriate.
The 2 extra ticks of affliction are extremely likely to be lost to other runemages casting affliction or yourself if you are keeping up 3 afflictions / 2 5% dmg debuffs. If the frost increased the duration of the affliction 5% damage debuff, then it would also be great incentive as this would give you more time to avoid casting affliction in favor of more fireballs (thus a damage increase as frost/affliction is a damage decrease).
What would be a good change? Runic diversity empowers your next spell (4th) rather than the 3rd.
Or, affliction dot damage also should receive the damage benefit, not just the initial impact.
Regardless if runic diversity can be made useful or not, or replaced. It’s counter-intuitive right now.
