Warlords Ability Pruning (bit of old news)

Priest
Priests received several significant changes, mainly focused on reining in Discipline's damage absorption shields, improving quality of life for Discipline and Holy specializations, and solving single-target damage issues for Shadow.


Ability Pruning
See the Ability Pruning section above for discussion of why we’re pruning class abilities. For Priests, pruning focused on removing redundant off-role abilities, trimming cooldowns, and removing niche abilities.

Binding Heal is now only available to Holy Priests.
Evangelism is now available only to Discipline Priests.
Hymn of Hope has been removed.
Heal has been removed.
Inner Fire has been removed.
Inner Focus has been removed.
Inner Will has been removed.
Rapture has been removed.
Renew is now available only to Holy Priests.
Shadow Word: Death is now available only to Shadow Priests.
Discipline and Holy Priests can add a self-damaging utility to Holy Fire through a new Major Glyph.
Spirit Shell is now a level-75 talent, replacing Divine Insight for Discipline Priests.
Strength of Soul has been removed.
Train of Thought has been removed.
Void Shift has been removed.
Ability Consolidation and Refinement
Priests had quite a few bits of complication strewn throughout their spells which we polished out.

Greater Heal has been renamed to Heal.
Borrowed Time’s effects have been merged into baseline Power Word: Shield for Discipline Priests.
Borrowed Time has been redesigned. It now increases the Priest's stat gains to Haste from all sources by 40% for 6 seconds.
Devouring Plague now always costs 3 Shadow Orbs, and now heals the Priest for 100% of all damage it deals, instead of healing per tick.
Holy Fire now lasts 9 seconds (up from 7 seconds).
Shadowform no longer allows any healing spells to be cast but also no longer has a restriction on casting other Holy spells.
Vampiric Embrace now heals all party and raid members for 10% of damage done, and this healing is no longer split between targets (up from 75% of damage done, split between targets).
Lightwell’s healing effect is no longer canceled if the target takes enough damage.
Pain Suppression no longer reduces the target’s threat by 5%.
Dispersion and Vampiric Touch no longer restores mana.
Base mana regeneration rate for Shadow Priest has been increased by 200%, Shadow Word: Pain and Vampiric Touch mana costs have been reduced by 50% to compensate.
Evangelism no longer affects the damage or mana cost of spells. Damage of affected spells have been adjusted to compensate.
Shadow Word: Pain’s initial damage is now considered direct damage, not periodic damage.
Shadowy Apparitions and Shadowy Insight are no longer able to trigger from this initial direct damage.
Divine Hymn now heals all party or raid members instead of a variable number depending on raid size. Its healing has been adjusted to compensate.
Focused Will now triggers from any damage taken instead of being limited to being the victim of any damage above 5% of total health or being critically hit by non-periodic attacks.
Level-90 Talents and Atonement
Atonement was the original damage-to-healing conversion ability, but grew out of control during Mists of Pandaria. We decided to reduce its effectiveness, to bring it more in line with our goal of it being an option to trade significant healing for significant damage (ending up somewhere between a full healer and a full damage dealer). Another place where Discipline's absorbs were too strong was in their interaction with the level-90 Talents, especially in large Raids. Near the end of Mists of Pandaria, we uncapped the AoE healing of that Talent row; that has proven to be a mistake in Discipline's case, not just because it caused the level-90 Talents themselves to heal for too much, but rather because the gigantic overhealing that that produced translated into gigantic Divine Aegis absorbs.

Atonement now heals for 25% less than before.
Cascade’s Mana cost has been reduced by 67%.
Discipline and Holy: Cascade now has a 1.5-second cast time (up from instant cast, see also: Instant Cast Heals), heals for 50% less, and no longer damages enemies.
Shadow: Cascade no longer heals allies.
Divine Star’s Mana cost has been reduced by 67%, and now follows standard AoE capping rules.
Discipline and Holy: Divine Star now heals for 50% less, and no longer damages enemies.
Shadow: Divine Star no longer heals allies.
Halo’s Mana cost has been reduced by 67%, and now follows standard AoE capping rules.
Discipline and Holy: Halo now has a 1.5-second cast time (up from instant cast, see also: Instant Cast Heals), heals for 50% less, and no longer damages enemies.
Shadow: Halo no longer heals allies.
Holy Changes
For Holy Priests, our biggest concern is with the Chakras. We think that Chakras are the defining abilities of Holy Priests, but that they haven't lived up to their potential. We decided to move more of their effectiveness from their raw throughput buff (which felt like a penalty for being in the wrong chakra, rather than a bonus for being in the right Chakra) into their bonus effects, and the Holy Word spells that they grant. Please note that all Priest healing spells have been retuned to account for the loss of throughput increases from Chakras. We also returned Renew to a normal 1.5-second global cooldown (GCD), so that Renew blanketing is still possible, but less ideal without Haste. Finally, the ability for Power Word: Shield to critically strike or Multistrike is now baseline for all Priest specializations instead of just Discipline so that it continues to be a viable choice for Holy at higher gear levels.

Divine Providence is a new passive ability for Holy Priests.
Divine Providence increases the amount of the Multistrike stat gains from all sources by 5%, and increases the damage and healing of Multistrikes by 20%.
Cascade no longer refreshes the duration of Renew for Chakra: Serenity.
Circle of Healing's cooldown is now 12 seconds (up from 10 seconds).
Chakra: Chastise no longer grants a chance for Smite to reset Holy Word: Chastise’s cooldown.
Chakra: Sanctuary no longer increases healing of area-of-effect spells. It now causes healing spell casts to reduce the remaining cooldown on Circle of Healing by 1 second instead of always reducing the cooldown by 2 seconds.
Chakra: Serenity no longer increases healing of single-target spells.
Power Word: Shield may now critically strike or Multistrike.
Divine Aegis no longer grants Power Word: Shield a chance to critically strike.
Divine Fury has been removed. (See also: Hit and Expertise Removal.)
Holy Word: Sanctuary now heals for 60% more than before.
Holy Word: Serenity now heals for 40% more than before.
Power Word: Shield now has a chance for a critical effect based on critical strike chance and can Multistrike based on Multistrike chance for all specializations.
Purify, Halo, Cascade, and Divine Star can now be cast while in Spirit of Redemption form.
Rapid Renewal no longer reduces the global cooldown of Renew.
Shadow Changes
Shadow Priests had one large problem toward the end of Mists of Pandaria: single-target damage. Their AoE and multi-DoT damage was some of the best around, so they still ended up competitive on most fights. But, in any fight that was mostly single-target, they felt lacking. Additionally, one of the new stats we're adding in Warlords of Draenor, Multistrike, is almost exactly what their current Mastery, Shadowy Recall, does for DoTs. So, we took these two problems and came up with a change that we think will solve both of them. The result is a new Mastery, which primarily increases single-target damage. Shadow Priests who want to focus on single-target damage can aim for Mastery in their gearing; or, when multi-dotting is more valuable, prefer other secondary stats over Mastery.

Shadow Priest’s Mastery (Shadowy Recall) has been replaced with a new Mastery: Mental Anguish.
Mastery: Mental Anguish: Increases the damage of Mind Blast, Mind Spike, Mind Flay, and Mind Sear by 20%.
Devouring Plague now always costs 3 Shadow Orbs.
Spiritual Precision has been removed. (See also: Hit and Expertise Removal.)
The cooldown of Mind Blast has also been adjusted to make Haste more valuable for Shadow, and removes Haste breakpoints.

Mind Blast’s cooldown is now reduced by haste, but its base cooldown is now 9 seconds (up from 8 seconds).
Talent Revisions
Several talents were split into different versions by specialization. We revised the effectiveness of some of these talents to better balance talent choices on their row. We also swapped the Level-15 and Level-60 talent rows so players are presented with core Priest themed abilities earlier in the leveling process.

To get back to a balanced place, we've reapplied the AoE caps to the level-90 Talents, making them consistent with all other AoE heals, and reduced their effectiveness across the board. We’ve compensated for this in the tuning of Priest baseline heals.

Level-15 and Level-60 talent rows have swapped places.
Divine Insight’s effects have been split based on specialization.
Discipline: The effect is now based on Spirit Shell.
Shadow: This effect is now named Shadowy Insight.
From Darkness, Comes Light has been split into two abilities depending on the Priest's specialization.
Surge of Darkness (Shadow) now has a maximum of 3 charges (up from 2) and can now also trigger its effect from Devouring Plague, but its chance to trigger has been reduced to 10% (down from 20%) to compensate.
Surge of Light (Discipline, Holy) activation chance has been reduced to 8% (down from 15%).
Power Infusion now grants 25% Haste (up from 20%), but no longer increases damage (down from 5%).
Solace and Insanity has been split into Power Word: Solace for Discipline and Holy, and Insanity for Shadow.
Insanity has been changed to cause consuming Shadow Orbs to transform Mind Flay into Insanity for 2 seconds per Shadow Orb consumed.
Twist of Fate now only triggers from healing for Discipline and Holy Priests, and only triggers from damage for Shadow Priests.
Miscellaneous Changes
First, there are a couple of quality-of-life changes for Prayer of Mending and Angelic Feathers. Next is a fix for a problem with Void Tendrils, where it lasts its full duration against creatures that had no way to attack it, such as in certain Raid encounters (note that the health reduction is to keep it where it was in health, compared to player health doubling). We also removed the Mana generation from Shadowfiend, in order to simplify it to being a burst-damage-cooldown. And last but certainly not least, we're making Holy Nova an efficient AoE healing spell for Discipline Priests.

Angelic Feathers now increases movement speed by 60% (down from 80%). If cast on players, will always prefer the casting Priest over others, then pick the player closest to the targeted location. If there are no players where it is targeted, it will still create a feather that can be picked up, as before. Additionally, when collecting multiple feathers, the duration will be extended instead of replaced; up to a maximum of 130% of base duration.
Enlightenment is a new passive ability for Discipline Priests.
Enlightenment increases the critical healing chance of Prayer of Mending by 10%, and increases stat gains to Critical Strike from all sources by 5%.
Holy Nova is no longer available through a Major Glyph, and is instead a Discipline specialization spell. Its mana cost has been lowered and its healing increased. It is intended as the efficient area-of-effect (AoE) healing spell for Discipline Priests.
Prayer of Mending from multiple Priests can now be on the same target, and can be on multiple targets from the same Priest, but the ability has a 1.5-second cast time (up from instant cast). (See also: Instant Cast Heals)
Shadowfiend no longer restores mana.
Mindbender now restores 0.75% mana per hit (down from 1.75% mana).
Void Tendrils now have 10% of the Priest’s health (down from 20%), and damage dealt to the rooted target is now also dealt to the Void Tendril itself.