Note: I am Nysem of Mal'Ganis now.
Hello everyone, and welcome to Lux et Umbra. This is a guide for Priest-related game mechanics. It is intended to be a guide to how stuff works while also functioning as a handbook of compiled factual information and numbers for all priests, new and old, pve and pvp, healing and shadow. If you're wondering about the thread title, "Lux et Umbra" is a Latin phase meaning "Light and Shadow." I hope the information contained here is helpful to everyone, as I have a lot of fun rewriting it and adding things as the game changes.
Special thanks to Nightshroud for writing the original version of this thread, Constie for his update of the original thread as well as his assistance in updating it once more, Dusknoir for fact checking, and everyone else that isn't mentioned here but did something that they feel contributed!
Table of Contents
I. Stats and Stat ratings
II. Spell, talent, glyph, and racial notes
This section outlines stats that are useful to priests, what they offer, and how they work. Priests will find Stamina, Intellect, Spirit, Critical Strike Rating, Haste Rating, Mastery Rating, Multistrike, Leech, Versatility, and Avoidance to be useful.
In WoD, stats are categorized into three types:
- Primary stats are those such as Intellect, Strength, etc (Intellect is the only primary stat you want).
- Secondary stats include Crit, Haste, Mastery, Multistrike, Spirit, and Versatility.
- In WoD, there is a new category called minor (aka tertiary) stats which includes Leech, Speed, Avoidance, and Indestructible. These stats may randomly appear on PvE gear drops, meaning some "Swords of 1000 Truths" will have them and others will not.
Spell power and Intellect
Intellect is converted into Spell power at a 1:1 ratio. Spell power will then increase the effect of your damage and healing spells by an amount determined by what's referred to here as the spell power coefficient of each spell. For example, the coefficient of Smite is 92.44%; If you have 4000 spell power, then Smite will deal (4000 * 0.9244) = 3697.6 damage. In WoD, most spells have had their base values removed so that the damage/healing (before buffs/passives) is determined only by their spell power coefficient. Some spells do appear to still have base values, so there may be more on that later.
Spirit and Mana Regeneration
Passive mana regeneration, or Mana per 5 seconds, is where priests receive a significant portion of their mana regeneration. All players have a base rate of mana regeneration, but that amount is directly increased by Spirit. The formula is 2% mana per 5 seconds baseline + 4.12207024 mp5 for every point of spirit. Holy and Discipline Priests find this useful as it becomes more difficult to run out of mana and allows the use of expensive spells more often. Shadow Priests do not have a use for spirit.
For Holy and Discipline Priests, the Spirit based portion of your regeneration is reduced to 50% when in combat. The formula for mana regeneration in combat then becomes 2% mp5 baseline + 2.06103512 for every point of spirit (notice the spirit portion is cut in half). Shadow Priests do not have any spirit based regeneration in combat, they will only regenerate the base 2% mp5.
Despite having no spirit based regeneration, Shadow Priests are not concerned about mana when performing their rotation - damage spells cost microscopic amounts of mana and your base mana regeneration will regenerate much faster than you can possibly spend it doing damage. So what function does mana serve for Shadow, then? Currently its purpose is to limit the use of certain spells such as Flash Heal and Mass Dispel without adversely affecting your ability to deal damage.
Fun Fact: Given the rate of mana regeneration, it is possible to convert other effects, like trinkets, that regenerate mana into mp5 (any value of mana per time is fine as long as you use the same units) to make easier comparisons when making gear choices. Power Word: Solace is an easy example. Under ideal conditions you may use it 6 times per minute, for 12% mana per minute, which is 1% mp5, which at level 100 means 1600 mp5 (1% of a 160k mana pool). 1600 mp5 divided by the value of a point of spirit in combat (2.06103512 mp5) comes out to Power Word: Solace being equivalent to 776.3 spirit when used optimally.
Mastery is a stat granting an effect depending on your specialization. For every x mastery rating you have, you gain an additional percentage of your spec's mastery bonus (The value of x depends on what spec you are as well). As you gain more mastery, the Mastery effect that you learned becomes more effective, such as a Holy Priest's Echo of Light. The tooltip displays a rounded number, so if you gain 1 mastery rating and the tooltip doesn't change, that point of mastery is still working.
Mana pools and mana costs
Spells don't actually have fixed mana cost numbers, but rather cost a certain percentage of your mana pool. Both mana cost and mana pools are numbers determined by class (Spec for some classes), level and nothing else.
Talents or effects that passively reduce mana costs apply to the base mana costs of spells, and stack additively; The mana cost reduction from Power Infusion stacks multiplicatively with others because it's an active effect as opposed to a passive one. However all the passives have been pruned out of the game, so there is that.