Unless something major happens, at this point of time Shadow Priests will stay as they are, which means that it's a prime time to have a 6.0+ guide.
[Table of content]
 Main section
1.1) Changes between 5.4.7 and 6.0.0 patches
1.6) Other changes that concern us
1.7) Arena compositions
Hello. For those of you who don't know me, I'm a 9x titled, 2900 experienced Shadow Priest who quit in Cataclysm and returned in S15 for casual play in preparation for WoD, where I intend to play full time again. I also have 3x Glad titles as a Warlock, and I used to be a really bad Rogue ( :) ). Most of my time I've spent on Stormscale ( old EU-Cyclone ) and Frostwhisper ( old EU-Rampage ), and after S7 I've resided on Kor'gall ( EU-Cruelty ), which turned into a massive battlegroup due to massive transfers in S8/S9 to a guild I was the GM of. I've been playing a Shadow Priest on both live and beta extensively these past few weeks, and I'm excited for what WoD is bringing to the table, both Shadow Priest wise and in general.
- Inner Fire and Inner Will are no more. RIP
- Renew and Binding Heal have been removed from the spec, RIP
- Prayer of Mending has a cast time
- Psychic Scream is now a talent, replacing MoP's Psyfiend ( good riddance ). Also now has a 6 second duration and a 45 second cooldown, belongs to DISORIENT DR category and DRs with plenty of other CCs ( more on that later )
- Dispersion, Shadow Fiend and Vampiric Touch NO LONGER RESTORE MANA. Shadow had its passive mana regen upped, and can now completely ignore the mana bar ( unless Flash Healing often )
- Holy Nova can no longer be glyphed, and is a Disc/Holy exclusive spell now. ( not that it matters, as it wasn't used much at all, if at all, but still )
- Mastery has been replaced - Mastery now flat out increases damage done by Mind Blast, Mind Spike and Mind Flay
- Psychic Horror no longer Disarms, and now belongs to INCAPACITATE DR category
- Devouring Plague now consumes 3 Shadow Orbs, you don't have the ability to use with less Orbs as you could before
- Vampiric Embrace has been lowered down to 10% ( 20% with the Glyph )
- we have lost the Dispersion set bonus, and instead need to glyph into Dispersion movement speed again
- Angelic Feather speed has been lowered to 60%
- LVL 100 ( 90+ ) changes that have yet to happen :
- we will now have the maximum of 5 Orbs instead of 3, with no ability or spell consuming more than 3 orbs at time. Leveling perk.
- Shadow Word: Death will ALWAYS generate a Shadow Orb, regardless of any circumstance ( this mainly goes towards its reset when it fails to kill a target ) - leveling perk
- Mind Flay recived an additional tick, and in return deals damage 33% faster - leveling perk
- Power Word : Shield will have its Weakened Soul debuff reduced by 5 seconds - leveling perk
- 2 set Shadow bonus : 1950 Versatility for 10 seconds after Dispersion ends
- 4 set Shadow bonus : Psychic Horror will refund Shadow Orbs spent on the ability, at the rate of 1 Shadow Orb / 3 sec
- Psychic Scream is now a 30 second cooldown instead of a 45 second cooldown
- Shields are absorbing less than they did in start of expansion ( I believe they got nerfed for 15% totally since the release ? )
- Cascade got immensely buffed, alongside with Auspicious Spirits
Talents have been rearranged, and 3 new talents have been added for level 100.
Tier 1 used to be the CC tier, now it's the defensive tier. The options are clear, a 22% instant cast heal on a 2 minute cooldown, a in-combat Stealth on 30 second cooldown, or a Priest variation of Cheat Death that yields a shield.
The choice falls down on you, the player, but in most situations, Spectral Guise is a clear winner. Not only does it allow you to do things you couldn't do otherwise ( sometimes avoid Rogue/Mage/x openers, have a unpredictable opener yourself, etc ), but Shielding yourself and Spectral Guising will usually net your healer more time to pick you up, resulting in a bigger effective defensive ability than both of the other talents combined. However, they do have a situational use and I'm sure some players won and will win games thanks to them, but those are rare and situational at best.
Verdict : take Spectral Guise
Edit : 12/04/2015 ( patch 6.1.2 ): I've started using Angelic Bulwark versus certain comps. Spectral Guise is still the best talent in this tier if you can properly use it, however versus certain comps ( jungle comes to mind ), you'll be permamently faerie swarmed and won't be able to get maybe even a second out of Spectral Guise. Again, Spectral Guise IS _THE_ talent to use in this tier, however, as I've said, Angelic Bulwark CAN work versus some compositions.
The mobility tier. You have a choice between a talent that increases your speed when you shield yourself, a talent which lets you drop Feathers on the ground for use by both you and your team mates, or Phantasm, a root+snare remover and mini-freedom.
Body and Soul immediately goes out of the picture, when there's a superior talent present ( Angelic Feather ). The choice boils down between Feather and Phantasm. Angelic Feather got nerfed to 60% in 6.0.0 - before the patch, you could Angelic Feather yourself while slowed with Crippling Poison/Hamstring/etc, and Angelic Feather and whatever snare effect you had on yourself would cancel out, meaning that you'd move at your usual movement speed ( 100% ) - however that's not the case anymore with Feather's nerf to 60%, meaning that Phantasm will once again play a role as a viable talent.
Verdict : completely up to you, as long as you ignore Body and Soul. Feathers will be the superior choice if you play with classes that can provide you with the Blessing of Freedom effect ( immunity to slows and roots ), while Phantasm will find its use in comps which do not provide you with said effect. Pick depending what comp you are running and what comp you're facing.
p.s. Angelic Feather into Spectral Guise is still a thing, happy fearing people
Single target damage tier.
Surge of Darkness now has a chance to proc off both Vampiric Touch and Devouring Plague, and can now accumulate up to 3 charges ( up from 2 ), which is a pretty decent buff. Mindbender provides your Shadowfiend with the ability to restore mana ( ordinary Shadowfiend does not do that anymore ), and a bit of extra damage on a lower cooldown. Insanity now procs from any Shadow Orbs consuming mechanic, and uses the 2 sec/shadow orb consumed formula to determine the buff duration, during which your Mind Flay deals extra 100% damage.
There's no clear winner here. All three are viable, and you can't go wrong. However, due to the nature of the game come WoD, where instant casts are highly favoured ( due to the melee nature of the game ), Surge of Darkness and Mindbender feel a little bit better than Insanity, as I haven't found myself in too many situations where I've been able to sit and freecast.
Entirely up to you.
Edit : 08/12/2014 : Insanity is plainly not viable in arena. Surge of Darkness or Mindbender. Mindbender is a liability because of possibility of him being CC'd by aoe CC such as howl etc. during your burst sequence, but I've found Surge of Darkness procs just going into my ordinary rotation and not being extra helpful during kill sequences.
The CC tier. Recieved the most overhaul with removal of Psyfiend ( and subsequent addition of Psychic Scream, /sigh @ Blizzard )
Void Tendrils still root the target until they're killed, but now have the added effect of breaking on target damage too. Psychic Scream has been nerfed to 45 second cooldown, and now lasts 6 seconds instead of 8 ( now lines up perfectly with your Silence though, meaning landed Fears will actually be more scarier for the enemy team as you'll always be able to Fear into Silence ). Dominate Mind is unchanged.
You'll pick Psychic Scream in 90% of situations. You are pidgeonholed into playing with Psychic Scream as long as you're playing with partners that don't have access to disorient CC category themselves. The other 10% of time, you'll be playing with someone the likes of a Warlock, meaning that, depending on Warlocks own choices, you'll be able to play with Void Tendrils instead.
Edit : 08/12/2014: There are situations where you can pick tendrils over Scream when playing with a druid. Other than that, the above largely remains unaltered.
Second damage tier.
Power Infusion is very very powerful paired with the new Insanity talent. However, as I've already said, chances of you being allowed to freecast whenever you want versus anyone decent are slim to none, whereas Shadowy Insight got buffed and now has a chance to proc off Mind Spike as well, having a clear synergy with Surge of Darkness from tier 3.
Choice is between Power Infusion and Shadowy Insight. It's entirely up to you, again. I prefer Shadowy Insight, although I've grown to not care about it due to Clarity of Power ( level 100 talent, explained a few tiers below ), so I've been meddling with Power Infusion lately. I like both, feels more like a flavour choice than anything. Your call.
Edit : 08/12/2014: Shadowy insight is garbage, Power Infusion is situational. Right now, if you're playing Godcomp or RPD, you're setting up 100-0 kills in CC, making Twist of Fate a really good talent because it makes you hit like a truck after people drop below 35%. Mindblast, Devouring Plague, 2x SWD = a target is dead unless you get CC'd, they're under cooldowns or they're outranging/LoSing you.
Edit : 12/04/2015 ( patch 6.1.2 ): Twist of Fate is your default go-to choice in arenas. For RBGs you have two choices. Obvious one is, again, Twist of Fate - you can almost permamently keep it up. Other choice is Shadowy Insight - you'll be drowning in orbs from Auspicious Spirits ( last talent tier ), however Shadowy Insight can find its use. Personal preference.
Aoe damage tier.
The biggest change in this tier has been the removal of healing on all of the spells.
Cascade is still a pretty bad choice ( again, same deal as with Twisted Fate - it's awful for arena, but pretty insane in rated BGs ), pitting you between Divine Star and Halo. Both talents still break CC ( or at least did few days ago when I've tested ), with Halo doing more damage but being less controllable, to Divine Star doing less damage but being more controllable ( also breaks enemy stealth/invis, unlike Halo ).
Up to you. Can't go wrong with both, but as much as I like Halo, I still pick Divine Star more often. The positive side of picking Halo before was the healing effect, as it could crit up 100k+ if cast from maximum range. Seeing it does not do that anymore, Divine Star seems like the logical choice most of the time. It's more controllable and castable more often, breaks stealth, etc.
Edit : 08/12/2014 : Halo.
Edit : 12/04/2015 ( patch 6.1.2 ): Use Divine Star for arena, and use Cascade in RBGs.
Level 100 talents tier.
Your choice here will lie between Clarity of Power and Auspicious Spirits. Void Entropy has been an absolute garbage of a DoT so far, both in PvE testing and PvP gameplay.
Auspicious Spirits will potentially work in a combo such as Shadowplay, where you want to spread your damage and simply PvE. It synergizes extremely well with all talents as well ( both Surge of Darkness+Shadowy Insight and Insanity+Power Infusion work very very well )
However, clear winner of this tier is Clarity of Power. It basically defines Shadow Priests on level 100 in PvP, and makes them into a great spec they feel like on beta right now. Insant Mind Blast on a 3 second lower cooldown is HUGE, and 40% extra damage on swaps is also huge. Storing Spike Charges and making a quick swap proved very deadly on beta, especially with Horror Orb regeneration effect from 4set PvP bonus.
You'll want to take CoP in almost every instance possible, clear winner.
Edit : 12/04/2015 ( patch 6.1.2 ): Clarity of Power in arena, Auspicious Spirits in RBGs.
NEW glyphs :
- Glyph of Delayed Coalescence - I've found a lot of uses for this Glyph, as it pretty much allowed me to survive situations where I would've otherwise died ( shield - 9 seconds dispersion when shield gets broken - weakened soul expires 1 second after Dispersion ends with this glyph; shield again , only to mention a possible use; your healer will love this glyph because with the removal of all the CC from the game, people won't randomly toss around CC and just go ultra aggressive whenever they feel like it, they'll start CC chains more properly and it'll be harder to avoid some than before - this glyph is designed for such situations, where you can't count on your healer for 10+ seconds )
- Glyph of Free Action - old Shadow PvP set bonus, nerfed from 60% to 30%. Might find uses, but seeing you can simply Angelic Feather into Dispersion in most situations, this is a flavour choice
- Glyph of Mind Harvest - currently really good on live 2s, however I don't see much use outside of it. On 100, Clarity of Power takes care of orb generation, and as such, having 6 second extra cooldown on Mind Blast during the entire arena game for a better opener really isn't worth it ( outside of very quick 3s games, I've found it useful versus triple melee teams )
- Glyph of Restored Faith - the best thing added in the expansion. This allows you many plays otherwise impossible, and allows you to have an upper hand on melee teams ( that will be quite prevalent in WoD ). Must have.
- Glyph of Silence - Before I mention what I found about this Glyph, keep in mind that Psychic Scream is now a 45 second cooldown ( gg Blizzard ... ), the EXACT same cooldown as unglyphed Silence. This allows you to line up EVERY Psychic Scream together with a Silence, I don't even need to tell you how powerful that is. However, this Glyph can still be good. A 3 second duration Silence on a 20 second cooldown ? This will be VERY good if you're playing a comp with CONSISTENT pressure, and it'll make enemies sweat if you have kill opportunity windows that DO NOT rely on you landing Psychic Screams - in such situation, this Glyph is amazing.
The following are the glyphs you'll find yourself using in arena :
- Glyph of Fade - it's still very useful in WoD, however, unlike in MoP, there are other viable contenders for its spot
- Glyph of Mass Dispel - very good against Paladin ( Divine Shield/Blessing of Protection ) and Warlock ( Dark Bargain ) teams, and decent versus Mage ( Ice Block ) teams
- Glyph of Mind Blast - your hidden trump card. We'll have a pretty decent amount of crit in WoD, and a 4 second root on Mind Blast crit ( extra synergy with Shadowy Insight+Clarity of Power ) is something that will be very very good against melee teams
- Glyph of Psychic Horror - allows you to use your Psychic Horror spell more often. Considering Psychic Horror now refunds your Shadow Orbs used on the spell itself, this became a very viable and decent option. Might see people stacking this Glyph with Glyph of Silence, because our only CC has been nerfed from 23 sec cooldown to 45 second cooldown.
- Glyph of Delayed Coalescence - no explanation needed here, if a certain team has a tendency to create a huge lockdown on your healer, this proved very useful
- Glyph of Restored Faith - in my opinion, a must have - it's a Priest version of Warlock and Monk portal; Mage Blink, etc.
- Glyph of Silence - situational at best, but in a world where all 3 of your CC spells are 45 second cooldown, might prove very good in comps that have high pressure and have kill opportunity window open often
- Glyph of Vampiric Embrace - the worst out of all listed viable glyphs, but it can find its use.
- Glyph of Weakened Soul - seeing it stacks with the leveling perk, you'll get 8 second cooldown shields. PWS isn't all that amazing, but it's still a very useful spell, especially with the removal of Renew - this allows you to be of extra help to your team mates when they need it
There's no clear verdict on the Glyph situation, however it seems that Glyph of Restored Faith will be a FOTM choice, whereas other Glyphs will be used by personal preference. I myself rolled with Restored Faith/Mind Blast/Glyph of Weakened Soul, and swapped Weakened Soul with Mass Dispel when versus teams with immunities; I've seen other Shadows roll with different setups, all seemed to work. Only constant was : Glyph of Restored Faith.
Edit : 08/12/2014: Glyph of Restored Faith is useful only on Z axis maps versus melee trains, otherwise it's better to have the default ability for your Rogue/Mage/Druid partner ( it's a safe bet to take the glyph versus Rogue teams btw, especially stuff like RMP or RMD that insist on training you to the ground ) you. Typically, roll with Psychic Horror, Fade and Mass Dispel. Swap Mass Dispel out for something else if you're not facing anything with a immunity magic debuff, I like to take Reflective Shield or Weakened Soul, depending what I'm facing.
Edit : 12/04/2015 ( patch 6.1.2 ): Default Glyph slots I'm rolling with are, as previously said, Fade, Psychic Horror, Mass Dispel.
You ALWAYS want to have Fade and Psychic Horror glyphs, the only glyph slot you'll be rolling around with will be Mass Dispel.
Versus RMD, swap to short Silence glyph.
Versus junglecleaves that like to train you, either swap to Dispersion ( 15 sec less on Dispersion ), or swap to Reflective Shield/Weakened Soul, whatever you think is more beneficial. If we're training the Feral, I almost always take Reflective Shield.
Versus turbo cleave, you can potentially swap to Psychic Scream glyph to make enemy Monk/Paladin stand in place, for your Mage to have an easier time landing sheeps, because fear can randomly fear someone to Africa and completely ruin your setup.
Anyway, as I've said, that 3rd glyph slot is modular. You can't expect to get reliable offensive dispels ( block, dark bargain ( if anyone even uses that ), bubble ), and you can't expect to get reliable defensive dispels ( cyclone ) that warrant this glyph. You might, you might not. Modular glyph slot, as already said.
( I've excluded the 6 abilites ( Vampiric Touch, Shadow Word : Pain, Mind Blast, Mind Flay, Devouring Plague, Shadow Word : Death ) found in "Core Abilities" section of your Shadow Priests spell book - they're sufficiently explained there - the only thing I'll mention is that Devouring Plague is recommended to be used "on CD" ( aka, every 3 Orbs built ) - however that's not the case in PvP. You need have a "feeling" when it's fine to use Devouring Plague and when you should simply save the Orbs, either for DP or for Horror - this comes naturally as you play the spec more )
- Dispel Magic - Removes 1 magic effect from enemies. One of best abilities we have, use it to strip down Resto Druid HoTs, Priest shields, beneficial buffs, etc - it has a limited use compared to how it used to be before, but it's still one of best spells in Shadow Priest's arsenal
- Dispersion - your "oh crap" button. Use when absolutely necessary, you want to delay using this ability as much as possible, because if you manage to save it when enemy team blew their cooldowns, it creates huge pressure on them. No longer restores mana, therefore only used when you need to mitigate damage.
- Fade - useless, unless you're using Fade glyph.
- Fear Ward - target this is placed on negates one Fear effect on them. Seeing this is Dispellable ( and more importantly, Spellstealable ), try to not pre-buff it, and instead cast it when you need it.
- Flash Heal - your healing spell. Not exactly super effective, but great when you need to help out on healing.
- Leap of Faith - this spell has two uses, depending on what glyphs you use. If you use no Glyphs, it pulls your partner to you. If you use Glyph of Restored Faith, it pulls yourself to your party/raid target. Both instances have great uses.
- Mass Dispel - very useful, even without Glyph. It dispels negative effects on your partners, allowing you to dispel a sheep/trap/etc every 15 seconds.
- Mind Sear - not used in arena for most part, except for keeping people behind a pillar in combat, or trying to stop a stealthed opener/trying to keep a stealther from stealthing.
- Mind Spike - used when you're locked on your Shadow school, or when Surge of Darkness procs
- Power Word : Fortitude - self explanatory.
- Power Word : Shield - spammed on cooldown in tight situations
- Prayer of Mending - used to be great, not so much with added casting time. Not useful unless facing a Death Knight or a Warlock team, where it'll bounce a lot.
- Psychic Horror - extremely useful spell - you'll be spamming this on cooldown if the opportunities present themselves, especially because it refunds 3 Shadow Orbs in 9 seconds after its usage
- Psychic Scream - I realise that this is a talent, but you'll be using it in 90% of cases, as it's your pidgeonholed talent choice ( extremely poor decision by Blizzard to put a core spell as a talent, and then to nerf it to the extreme as well ). You'll be using it on cooldown to create CC chains, both with your partners and on your own ( Psychic Horror and Silence )
- Shackle Undead - warrants a bind because of Death Knights. Shackle empowered Death Knight pets ( abominations ), and shackle gargoyles, it's more than worth the global.
- Shadowfiend - now a DPS cooldown. Pop it when you need extra damage during kill attempts.
- Silence - prevents enemy from casting for 5 seconds. Extremely versatile uses, and not only on healers - if you have a healer in CC and you're going for a kill on the DPS, you can use Silence
( * apparently Silence doesn't prevent Touch of Karma anymore, just tried it on beta, and it's true )
- Vampiric Embrace - pop when your team needs healing, but you're free to damage. This, combined with PW:S on cooldown, creates decent healing utility. Don't expect it to keep someone alive through hard damage, but it helps your healer out a bit when needed.
Alliance Priest races :
Humans remain the best choice when it comes to damage. You're still able to equip two PvP damage trinkets while keeping the PvP trinket ability ( Human racial ), providing you with the most damage in PvP out of every other Priest race in the game. However, it depends on quality of available trinkets, and is not worth being a Human if trinkets are not really good.
Dwarves became a viable choice with the Stoneform buff. It removes all poison, disease, curse, magic and bleed effects, and reduces physical damage taken by 10% for 8 seconds, all of that on a two minute cooldown. They're, as it stands, the best defensive race in the game that Shadow Priests have. This talent is great versus the likes of Rogue/Mage/x and various other comps that like to train the Shadowpriest. Synergizes well with Fade glyph, for 20% damage reduction on demand.
- Night Elf
Night Elves are the best when it comes to openers/defensive stealthing. Spectral Guising into a Shadowmeld provides both a decent offensive and defensive option. I've had trouble Shadowmelding stuff on beta, but it's still there, too, allowing a skilled Shadow Priest to avoid a CC altogether.
Gnomes and their Escape Artist are a decent option, however nothing overly interesting.
They have a HoT that heals for 20% health over 5 seconds, on a 3 minute cooldown. Situational at best.
Not really worth mentioning, as their racial is something you most likely already have as a talent ( Angelic Feathers ). It is however, very decent if you're using Phantasm.
Horde Priest races :
A classic choice, but one of the worst choices as it stands on beta. With Will of the Forsaken nerfed to 3 minute cooldown, and with Fear effects not being as prevalent in WoD, it gets easily outshadowed by other choices. Still, a decent choice, and a minor bonus being that Touch of Grave can proc off Multistrike procs.
Really good choice, especially if you're rolling with a Insanity oriented build ( Insanity-Power Infusion ), popping Power Infusion with Troll Berserk gives you a insane burst potential.
- Blood Elf
Best choice out of Horde races at the moment. Not only do you recieve passive 1% crit extra, but you also get Arcane Torrent, a AOE silence, which by the way, is one of four Silence effects still in the game - Silence, Garrote, Strangulate, and Arcane Torrent
Warstomp is decent, but nothing special. Not worth mentioning.
Second best Horde option, tied together with Trolls. Rocket Jump is insanely useful, especially in the melee oriented game that is WoD.
They have a CC that DRs with almost everything in the game now. Not a viable choice.
- Tremor totem got changed. Shamans can no longer drop it while Feared, and are now required to drop it before you Fear. This will create ( boring or interesting, we'll see ) mind games, but the end result is clear - if you land a Fear, you've landed it.
- Mages can no longer Deep Freeze you and deal damage to you while you're stunned. They can however Frostjaw or Ice Nova you instead, providing a similar effect. They also do not have a silence component on Counterspell, allowing you to immediately start casting Mind Spike after being interrupted by Counterspell.
- Warriors have lost Stun component on their Charge, allowing them to Charge-Pummel us ( which can sometimes be worse than being simply stunned, as it disallows use of Dispersion )
- Prayer of Mending now has charges, and acts as a dispel protection on the target you're trying to dispel
- Monks don't blanket silence you anymore when they interrupt you
- pulling yourself to a target via Glyph of Renewed Faith apparently breaks stealth openers from Ferals and Rogues. Managed to replicate it a few times, seems quite useful
- as I've already mentioned, Shadow lost its mana regeneration tools ( unless you're playing with a Mindbender ), and in return had its passive mana regen boosted so much that you don't really need to worry about mana at all anymore in most situations. However, be VERY careful if you drop form and start spamming Flash Heal, this CAN make you OOM very fast, and now you have no way to recover outside of waiting for mana regen to kick in, or drinking. Spamming Power Word: Shield and Dispel Magic can also make a dent in your mana bar, but nothing too significant.
- Psychic Scream now belongs to DISORIENT DR category, which means it now DRs with a lot of other CC it didn't previously DR with; notably with Cyclone, killing ( or crippling ) Shadow Priest/Resto Druid synergy
- Psychic Horror now belongs to INCAPACITATE DR category, which means that it now DRs with : Sheep, Trap, Sap&Gouge, Disorienting Roar, Hex, Mortal Coil, Shackle Undead, Repentance, Hibernate, Ring of Frost
Edit : 12/04/2015 ( patch 6.1.2 ):
Removed previous section.
Arena compositions :
GOD TIER ( aka top of the line comps that you can easily get Glad with if you're good enough ):
- Shadow Priest / Frost Mage / Resto Druid
- Shadow Priest / Frost Mage / Holy Paladin
TIER 1 ( aka, still Glad viable, with a little bit of effort, but not nearly as good as god tier comps ):
- Shadow Priest / Frost Mage / Mistweaver Monk
- Shadow Priest / Frost Mage / Restoration Shaman
TIER 2 ( aka, can work against SOME of the GOD/TIER 1 comps, but climbing the ladder might be super super hard because general meta of comps is not in your favour - basically unless you're the type of player who doesn't need to read this guide, don't expect success ) :
- Shadow Priest / Retribution Paladin / Restoration Shaman
- Shadow Priest / Combat Rogue / Restoration Druid/Shaman ( or Holy Paladin )
- Shadow Priest / Feral Druid / Restoration Shaman or Holy Paladin
- Shadow Priest / (?) Hunter / Paladin
On level 100, enchants and gems are a scarce resource. In WoD you'll be able to enchant necks, rings and weapons. I haven't come across of a way to enchant other pieces of equipment, but I haven't explored beta outside of arena. However from what I've heard - that's all there is to it. All the lower level enchants have been prohibited from being used on higher level equipment.
As for gemming, you have zero gem slots.
Professions also play no role whatsoever, because none of them have any combat-related perks anymore ( only exception being Engineering, but none of the Engineering toys work inside arena ).
Edit : 08/12/2014 : I'm personally enchanting Mastery on Neck, Back, Rings, and will enchant my S16 weapon with Mark of Bleeding Hollow. Although I'm contemplating Versatility on offpieces if our survivability gets too shit ( doubtful though ).
Edit : 12/04/2015 ( patch 6.1.2 ): Versatility on Neck/Back/Rings, Mastery on weapon. I've tried haste enchants, they're dogshit. Mastery gives you the most damage, but we don't really need more damage. Just roll with Versatility on offpieces, it's easily the best out of mediocre options.
http://www.twitch.tv/talbadar - r1 spriest
http://www.twitch.tv/khyrl - r1 spriest
http://www.twitch.tv/snutzy - r1 warlock that occasionally streams his shadow priest alt
http://www.twitch.tv/jahmillionaire - r1 spriest
http://www.twitch.tv/wizkx - r1 spriest
Will add more when I see any others.
/cast [target=focus] Silence
- casts Silence on your focus target
- all in one Shadowfiend macro. What this does is directs your Shadowfiend's attacks to the target you're attacking, and casts Shadowcrawl in case he acts stupid and doesn't use it himself ( :) ).
/cast [target=party1] Power Word: Shield
- Casts PW: S on your first party member. Replace party1 with party2 and etc to cast it on other targets
/cast [target=NAME] Fear Ward
- Replace NAME with whatever name of the person you want Fear Warded.
- I use this when I need to cancel Dispersion. Especially now, when it no longer restores mana, you shouldn't sit in it full duration unless you have to. Use it when it's important, cancel it when the trouble expired.
/cast [target=focus] Psychic Horror
- Horrors focus target
I'm of opinion that keybindings do not really matter, as every person should make up their own comfortable ones. However, too many people get lost when they're trying to set up an optimal setup when learning a new class, so I'm going to post my keybindings below for such usage. I'm in no way saying this is the optimal way to play a Shadow Priest, as I've already previously stated - keybindings don't matter, but this is what works for me, and some of you might find it useful.
1 - Shadow Word: Pain
2 - Mind Flay
3 - Mind Blast
4 - Shadow Word: Death
E - Devouring Plague
F - Vampiric Touch
¸(tilda) - Mind Sear
T - Halo/Divine Star
Q - Mind Spike
Shift+F - Shadowfiend/Mindbender
V - Angelic Feather
Mouse wheel down - Dispel Magic
Shift+V - Dispersion
Ctrl+F - Fade
H - Fear Ward
Mouse button 5 - Flash Heal
CTRL+Q - Leap of Faith
F1 - Levitate
X - Mass Dispel
Shift+Y - Mind Vision
F5 - Power Word: Fortitude
Mouse button 4 - Power Word: Shield
CTRL+ Mouse button 4 - Prayer of Mending
Shift+E - Psychic Horror
Shift+ Mouse button 4 - Psychic Scream
F7 - Resurrection
F3 - Shackle Undead
, - Shadowform
R - Silence
Shift+R - Spectral Guise
Shift+Q - Vampiric Embrace
F2 - Cannibalize
F4 - Mount
Shift+F4 - Flying mount
Mouse wheel up - Racial ability
Shift+Mouse wheel up - PvP trinket
Shift+Mouse button 5 - on-use damage ( trinkets, racials, abilities such as Power Infusion, etc )
Shift+S - water/water+food
Alt+E - Focus Horror
Alt+R - Focus Silence
Ctrl+1 - Shield Party1
Ctrl+2 - Shield Party2
Shift+1 - Focus arena1
Shift+2 - Focus arena2
Shift+3 - Focus arena3
B - Cancel Dispersion
5 - Fear Ward on myself
Y - Fear Ward on healer
This is very much so work in the progress, and I'll keep updating it whenever something new pops up. As for Shadow in WoD, I feel we're in a very decent spot. We're both fun to play, and very useful in arena - my only annoyance is Blizzard's shameless placement of Psychic Scream into Talents, thus pidgeonholing Priests into speccing Psychic Scream ( and not only that, it's been nerfed heavily as well ). Outside of that, I feel like they've done a very good job with the spec. Clarity of Power introduced a fun gameplay element that allows us to alleviate all the pressure melee classes had over us in the past, and unlike in MoP, we have steady Shadow Orb generation even while trained, and our mana isn't an issue anymore.
If you have any questions, don't be afraid to ask, both via PM or here.
02/11/2014 - added "Outside resources" section for useful links ; changed topic title to reflect 6.0.3 up-to-dateness
08/12/2014 - added minor changes to Talents, Glyphs, Arena composition sections to reflect the current state of Arena - by no means final.
12/04/2015 - added minor changes to Talents, Glyphs, Arena compositions. Updated for patch 6.1. Planning on adding tips & tricks for viable comps when I get the time.
Wowhead's Priest talent calculator
Chewthefat's post regarding DoT snapshotting
Lolflay's post on optimal gear setup in S16