Allright , finally got some time to explain the lowdown about our dps brothers. Like the holy and the discipline thread , this is only about optimizing raiding talent/gem/enchant/glyph for ICC10/25. I do not cover leveling-doing heroics-pvp & lower raid instances like Ulduar or ToC.

Over the 5 years of WoW , Shadow priest got the best and worst of class tweaking. While ridiculously overpowered in Vanilla WoW ( I actually tanked Onyxia p1 back then , guild was bored that one time hehe ) to the mana battery role we had in TBC ( our raid dps sucked back then but the mp5 buff was awesome ) , Shadow is actually is a good spot in WotLK at the moment and they bring a lot to a raid.

-Talent-

Like the disc priest , Shadow priest don't have a lot of choices when it comes time to put your talent points to good use because most of them are mandatory.

The ultimate cookie-cutter spec is : www.wowhead.com/talent#bVcbuZZGxfVRfz... This is the spec you should have 99% of the time but there's 1 option.

The "Godly" spec is : www.wowhead.com/talent#bVcbuZZGgf0Rfz... This spec is absolutely NOT for everyone because to make the most out of it , you need over 1000 haste + 4pc T10 bonus. At this point , Mindblast is out of your rotation as Mindflay hits much harder than any MB crits. You also burn mana faster ( hence 3 points in Focus Mind ) and you generate more threat (hence 2 points in Shadow Affinity ).

-Gems-

Where holy and disc priest can usually ignore the gemming color bonus on gear , Shadow priest gain the most by trying to stick to it.

• Red slot : Runed Cardinal Ruby ( +23 spellpower )
• Yellow slot : Reckless Ametrine ( +12 spellpower & +10 haste)
• Blue slot : Purified Dreadstone ( +12 spellpower & + 10 spirit )

The reasoning behind this is that SP > Haste > Crit > Int > Spirit . Wait a minute! Int & Crit are better than Spirit ? Then why the Purified Dreadstone ? Well , because there's no blue/purple gem with Int or Crit on them. Forget about green gems plz. You should never ever gem a pure blue or a pure yellow gem either( i.e. +20int , +20 spirit , +20crit , etc ). Your gear should handle your crit/hit/int needs.

-Enchants-

This is not an option .... spellpower all over but if you use a MH+OH combo , Black Magic is better than +63 spellpower. If you use a staff , stick with +81 spellpower. Boots is the only gear that cant have +spellpower enchant so go with Tuskar's Vitality or Icewalker ( if you are not hitcapped )

-Glyphs-

Shadow priest glyphs don't offer a lot of choices. The only one that is ABSOLUTELY mandatory is Glyph of Mindflay. For the other 2 major glyphs and the 3 minor glyphs , you have options. None of them are gamebreaking.

Major choices

• Glyph of Dispersion : It lowers the CD of Dispersion to 1 min 15 seconds instead of 2 min. Dispersion is an "oh shit " button mostly when raiding , the mana regen is really nice but you shouldn't Oom ever anyway. Can be used to ignore the spore stacking on Festergut (90% damage reduction is better than the 75% reduction you get with 3 stacks )
• Glyph of Shadow Word:Pain : Ticks of SW:P restore 1% base mana. Shadow Priest are not known to go out of mana ... EVER. Unless you are using the "Godly" spec , its pointless.
• Glyph of Shadow : While in Shadowform, your non-periodic spell critical strikes increase your spell power by 30% of your Spirit for 10 sec. Non-periodic spell is the key here. Its good if you have reasonable spirit on your gear and you cast Mindblast alot ( i.e. Cookie-cutter spec). Probably the best optional glyph there is. ( Althought not that good if you have below 400 spirit and/or are using the "Godly" spec )
  
• Glyph of Mind Sear : Increases Mind Sear radius by 5 yards. Good on trash for sure and on LK phase 3 where you need to AoE the vengeful spirit in the sky. Useless everwhere else.
• Glyph of Shadow Word:Death : Targets below 35% health take an additional 10% damage from your Shadow Word: Death spell. Sounds nice but how many shadow word : death did you cast lately ?

Minor choices

• Glyph of Shadow Protection : Increases the duration of your Shadow Protection and Prayer of Shadow Protection spells by 10 min.
• Glyph of Fortitude : Reduces the mana cost of your Power Word: Fortitude and Prayer of Fortitude spells by 50%. Can be useful if you need to recast it in combat because someone died ... but they shouldnt because they moved out of the fire patch , right ? :p
  
• Glyph of Shadow Fiend : Receive 5% of your maximum mana if your Shadowfiend dies from damage. Well , Shadowfiend are pretty resilient to start with but on occasion they can die ( big raid AoE for example like Precious's devastate)
  
• Glyph of Levitate : Useless in raid yet all minor glyphs are pretty much useless in raid so saving reagent is always nice.
• Glyph of Fading : Reduces the mana cost of your Fade spell by 30%. Prolly the best raiding minor glyphs.
  
• Glyph of Shackle Undead : Increases the range of your Shackle Undead spell by 5 yards. Unless you are trying the Full House achievement on Lady Deathwhisper , its pretty much useless. When was the last time you actually kept a mob CC'd ?
  

Bonus info

Ok what's the deal with haste ? Well , for spriest , haste scales really good. Probably the best scaling class on haste in the game atm. If you read the Shadowform tooltip , you'll notice that Devouring Plague and Vampiric Touch are affected by it ( doesnt affect SW:P tho ) and we have a channeled spell called Mindflay that benefits from it. Also a 1sec cast Mindblast is nice. But like our holy priest brothers , the real magic in haste relies in the lower global cooldown on every spell. Global cooldown is the base 1.5 seconds time you cannot cast another spell after casting any spells and YES it is affected by haste. The more you have , the lower is goes. There is a 1 sec hard cap on GCD tho so if you ever get there, haste becomes less valuable ( but that's around 1500 haste raing so dont worry about that for now ). Meaning that with over 1000 haste , you could cast VT+DV+MB+MF+SWP in the same amount of time than a spriest without haste would cast VT+DV+MB ..... now you know why haste is the definition of our class "Facemelting" nickname :)

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