On top of this you have the best aoe spell (damagewise) - Hellfire; and a situational one - Rain of Fire.
So, to sum it up, warlocks are:
- Dps kings
- Slacker helpers (summoners)
- Soulstone providers
- Health stone vendors
- Tank buffers
- The best aoe class when it comes to steady damage
First things first, let's start with your talent spec. There are a few good options, either of which work just as well (although some are a small bit better for dps then others).
SM/Ruin - This is pretty straight-forward, really. The best for all-around utility and almost maximum dps. Key talents are: Affliction - Improved Corruption, Improved Life Tap, Improved Curse of Weakness (if your guild requires using this curse, otherwise you can assign there points anywhere else you wish), Grim Reach, Nightfall, Shadow Mastery - and Destruction - Improved Shadow Bolt, Bane, Devastation, Destructive Reach, Ruin.
MD/Ruin - One of the best talent specs for high-end raiding, as you can easily switch from using a sacrificed succubus (maximum dps possible) to having a passive imp (or even one that shoots until its mana runs out) for the threat reduction. Depending on gear and your tank's ability to generate threat, this might be a better choice for 5-mans. This spec also works best if you're the warlock assigned to the tank group, due to having the ability to spec 3/3 in Improved Imp without passing on other talents. Key talents in the Demonology tree are Improved Healthstone, Demonic Embrace, Fel Domination & Master Summoner, Demonic Sacrifice and Master Demonologist.
DS/Ruin - The best dps spec there is, requires pretty high maintenance (at least one shard for each boss attempt). The key talents are pretty much the same as the ones stated before on other specs and you can almost always rely on topping dps charts with this spec and a shadow priest in the raid group. Do be careful not to overaggro though (salvation or tranquil air are a must). The downside is that while this will maximize your dps, it could be less beneficial to the group, as you're not providing Blood Pact.
Alright, now let's move on to your rotation. In most cases, if your guild is any good, you will not have to (nor should you) cast anything other then a curse + shadow bolts. Your warlock class leader (or the officer in charge of your class) should relay which utility curse each one of you should do (Elements / Shadows / Recklessness) and all others are free to use Curse of Doom. Why Curse of Doom? Because the only thing that does more dps is a Curse of Agony buffed with Amplify Curse. And if you're not SM/Ruin, you shouldn't be using CoA for dps on bosses.
Those specced SM/Ruin may also use Corruption, but only when instructed so by the leader. Due to the debuff slot limit being at 16 in vanilla, there are only a few debuffs allowed for dps'ers and generally those will be given to warlocks for Corruption. If you aren't SM/Ruin, let those specced this way use their Corruption for Nightfall procs.
Gear is a touchy subject usually and everyone has their ideas of what is best. I've always went by the rule that one should never aim for Stamina if they want to maximise dps output (that's your role in a raid and I trust you want to do it as best you can) and since you can rely on Life Tap for mana (and, in a raid, heals to top up your health), you can almost ignore Intellect altogether as a worthless stat - its major use is for the 1% crit chance per 60 Int it gives.
So what does improve your dps as a warlock? Shadow spell damage. And Spell critical hit chance. And Spell hit chance. That's it.
How much? Well, the game uses 2 formulas to calculate how much bonus your spells receive based on how much spelldamage you have on gear. These are:
- For instant-damage spells: Base damage + (untalented_cast_time / 3.5 seconds) x spell_damage
- For dots: Base damage + (dot_duration / 18 seconds) x spell_damage
What this means is that slower (or longer lasting) spells will benefit more from spell damage effects on gear, while faster ones will benefit less - so spellcrit would be better for these. Generally, for pre-raid gear, I approximate that 1% spellcrit is roughly equal to 1% spellhit and 15 spelldamage. Intellect is also noticeable here, as 60 int = 1% spellcrit and, thus, 4 int = 1 spelldamage. These are, however, highly dependant on the gear available to you and will change based on your current number (as you get more spelldamage, spellcrit and spellhit become more valuable).
Let me give you examples of both an easy-to-get and a best-in-slot pre-raid gearset you should be aiming for:
Head: Felcloth Hood (crafted, Tailoring) -> Spellweaver's Turban (General Drakkisath, UBRS)
Amulet: Anastari Heirloom (Stratholme - undead side) -> Diana's Pearl Necklace (Cannon Master Willey, Stratholme - living side)
Shoulder: Felcloth Shoulders (crafted, Tailoring) -> Lieutenant Commander's Dreadweave Spaulders (PvP) OR Abyssal Cloth Amice... of Sorcery (Baron Kazum, Silithus summonable)
Back: Amplifying Cloak (Magister Kalendris, DM West) -> Crystalline Threaded Cape (BoE - not recommended to farm for)
Chest: Robe of Winter Night (crafted, Tailoring) -> Robe of the Void (crafted, Tailor-only)
Wrist: Sublime Wristguards (Guards - DM North) -> Rockfury Bracers (Silithus - equal to Tier2 items, very much worth farming for)
Hands: Felcloth Gloves (crafted, Tailoring) - both easy enough to farm for and best-in-slot
Waist: Oddly Magical Belt (DM North tribute chest) -> Ban'thok Sash (Ok'thor the Breaker, BRD Arena)
Legs: Felcloth Pants (crafted, Tailoring) -> Skyshroud Leggings (Highlord Omokk, LBRS)
Feet: Shadoweave Boots (crafted, Tailoring) -> Maleki's Footwraps (Maleki the Pallid, Stratholme - undead side)
Ring: There aren't really that many good choices for rings, so if you get 2 of the following, consider yourself set for raiding - Don Mauricio's Band of Domination (Darkmaster Gandling, Scholo), Maiden's Circle (BoE, grab it off the AH if you see it), Eye of Orgrimmar / Songstone of Ironforge (BRD quest chain on either side)
Trinket: I will detail on each trinket, linking several options - Eye of the Beast (UBRS quest chain on either side - easy to get and also best-in-slot), Talisman of Ascendance (Argent Dawn epic reward - a pain to get, but it outshines all other trinkets because you can time it right so that your Curse of Doom / Amplified Agony benefits from the 5 stacks), Briarwood Reed (Jed Runewatcher, UBRS - also best-in-slot, on par with Eye of the Beast), Royal Seal of Eldre'Thalas (Harnessing Shadows, book turn-in quest in the DM library - easy to get trinket, will last you until one of the earlier mentioned trinkets comes your way)
Weapon: Staves - Soul Harvester (warlock class quest in Sunken Temple - almost best in slot for pre-raid, not worth rolling on the next one over this staff unless noone else can use it) -> Rod of the Ogre Magi (DM North tribute chest)
Off-hand Frills (optional, not worth using with any pre-raid one-handed weapon): Spirit of Aquementas (Linken quest chain, Un'goro Crater) -> Tome of Shadow Force (PvP, AV rep reward)
Wand: Bonecreeper Stylus (Darkmaster Gandling, Scholomance) / Ritssyn's Wand of Bad Mojo (Baron Rivendare, Stratholme - undead side)
For enchants, I would suggest going with 2x Libram of Focus (one for the headpiece, one of the leggings) and Intellect wherever possible (it gives 15 mana for each point vs 10 health for each Stamina point, therefore making the total mana pool bigger while also allowing more time to cast before you need to life-tap first).
Here's a list of consumables no real raiding lock should be without:
Flask of Supreme Power *3
Elixir of Shadow Power (alternatively, Greater Arcane Elixirs work too) * 40
Dirge's Kickin' Chimaerok Chops *20 (optional)
Heavy Runecloth Bandage *10
Greater Fire Protection Potion (amount depending on type of encounter - if needed for progression, at least 40)
Greater Nature Protection Potion (amount depending on type of encounter - if needed for progression, at least 30, usually 40)
Magic Resistance Potion (amount depending on the resist gear you already have, this will help a lot to reach the next level of resistance - suggested amount: 50)
Field Repair Bot 74A *1 (if you're an engineer)
Soul Shard *60
Wizard Oil *2 (10 charges)
General advice for dps:
On trash, in order to maximise dps output, try noting how long it takes for mobs to die with your current group. If they die faster than 75% of a dot's duration, then it's not worth putting that dot up, as the global cooldown lost doing so might have meant one more Shadowbolt (that would have done more damage). This is, of course, unless you're specced SM/Ruin and you need Corruption for Nightfall procs.
On bosses, if there are random sources of damage possible on you, try not to life-tap lower than 50% before you get your first heal. It might be more efficient to stop dps altogether and life-tap until you have nearly full mana, but you shouldn't continue to lower your health past the 50% mark if no healer has noticed you tapping (you risk death from boss abilities). Generally, it is also a good idea to life-tap once when you get to 70-80% mana (and you will receive full benefit of mana from the tap), so that your health regen from Demon Armor is put to good use - might also be worth mentioning that to the healers, so they don't panic and overheal you.
Don't underestimate the perks of sacrificing demons other than Succubus (obviously this applies to warlocks specced in DS/Ruin). A sacrificed voidwalker will regenerate a seemingly small amount of health which however can be great for fights that are long and unavoidably damage inflicting to everyone, but where you're threat capped anyway. The imp will also give you a +15% fire damage which can be great for AoE pulls. Combine that with some fire resistant gear and you have yourself the best available AoE in the game.
Should you find yourself playing in a raid with lots of warlocks, your imp is probably not going to be the best choice to go with (this applies to warlocks specced in SM/Ruin or MD/Ruin). The felhunter provides great utility to both yourself and the group being able to counterspell as well as dispel magic. Do not overlook these two abilities.
Last, but not least, since your rotation is so easy, you might want to consider putting Shadow Bolt keybound to mousewheel (up and down), since rolling the mouse wheel gives off signals a lot faster then keystrokes (especially for repetitive strokes). If you do this and then start rolling the wheel up or down while the last 10-15% of your current SB is casting, you will increase your dps by at least 5%, as the time between when the system considers the previous spell to have ended and the time when your next keystroke occurs will be shortened by having more signals sent to the game client.
Here's a macro you might find useful if you can't / don't want to / don't feel like peeking at your health bar every now and then to check if it's safe to tap. I would recommend that you keep your regular Life Tap spell on your bar, just in case you need that extra bit of mana and can't get healed back up over 50% OR the fight allows you downtime in which you can tap to full.
/run h=0 if UnitHealth("player")/UnitHealthMax("player") > [color=#ff0000]0.5[/color] then if UnitMana("player")/UnitManaMax("player") < [color=#0000ff]0.5[/color] then CastSpellByName("Life Tap") end; end;
If there is anything I missed or you have anything to add, please do so in a constructive way. I hope this helps any warlock maximise their potential and always do as much damage as possible in raids and outside them!