We warlocks have a litany of curses at our disposal, with wildly varying effects and durations. Fortunately for our targets, we can only land one curse per target, whether it's a straight-up DoT like Curse of Agony, or a debuff effect like Curse of Tongues.
Much of the Warlock's group utility and versatility are defined by our access to these various effects. While some curses have wider applications than others, it is hardly a one-curse-fits-all situation. Knowing which curse to use in the right situation is key to maximizing your Warlock's potential.
New Curse of the Elements
Come patch 2.4.3, one of our most important DPS-increasing debuffs - Curse of Shadow (CoS) - will be no more. It will have its effect merged with Curse of the Elements (CoE), resulting in a single curse that buffs Shadow, Arcane, Frost and Fire damage.
Merging these two sets of debuffs improves the utility and damage potential of each single Warlock and is great for small-group work like 5 and 10-mans. However the "stacking value" of each additional Warlock after the first or second is somewhat diminished in 25-man raids. All other things being equal, one Warlock will do the debuffing job of two when patch 2.4.3 goes live. This will mean that for an "optimized" raid, that last Warlock slot may now be open to other ranged DPS classes like mages, hunters, elemental shamans or even moonkin druids.
The value of the new CoE is obvious, improving the DPS potential of all mages, warlocks, shadowpriests, moonkins and even hunters in a raid. Malediction, deep in the Affliction tree, can further enhance the damage bonus effect of this curse by 3% - improving the affliction lock's utility in any raid.
So, when do I use these?
In a typical raid setup, at least one Warlock must be assigned "CoE duty". The overall raid DPS increase from the new CoE far outweighs the personal DPS loss of that Warlock by foregoing Curse of Agony or Doom.
Before patch 2.4.3 however, CoS generally takes precedence over CoE, unless you have more Fire/Frost than Arcane/Shadow DPSers in your raid.
Curse of Agony and Curse of Doom
The raw DPS of CoA is higher than CoD, but you'll still do more damage with the latter curse in fights that last longer than a minute. This is because of the time lost to global cooldowns when you refresh your CoAs.
So, when do I use these?
If you're not assigned to any other curse duties in a raid, use these.
In smaller groups, both these curses should make way for CoS (or the new CoE) in single-target situations if:
fights are too short for Curse of Agony or Doom to deliver their payloads, or
if you're Destro and there's at least one other toon (Warlock, Shadowpriest or Arcane Mage) in the group who can benefit from CoS.
If you're a deep affliction lock, you'd contribute more damage with amplified CoDs and CoAs in longer fights.
In soloing and farming work, Curse of Agony is preferred for its "fire-and-forget" utility in multiple mob situations.
Curse of Recklessness
This curse has gained prominence in raids by buffing physical DPS by about 6%. To make this curse count, the increase in melee and hunter DPS must be greater than what CoD or CoA can put out, which is typically about 150dps. The breakeven point is about three DPSers dishing out 900 physical dps consistently - most 25-man raid setups should have no problems surpassing this.
Curse of Recklessness (CoR) also has the negative effect of increasing the mob's melee attack power by 135. For bosses that rely on melee moves as their primary form of attack, CoR can be bad news for your tank.
So, when do I use this?
With CoS merged into CoE, a second Warlock can be assigned to apply CoR on the raid's target in selected encounters. CoR is best used on non-melee mobs that deal ranged or magical damage, and is mostly safe for trash mobs. The increased AP can be somewhat cancelled out by a Warrior's Improved Demoralizing Shout or another Warlock's Curse of Weakness (see below), and an affliction lock's Shadow Embrace effect.
In fights where survivability, especially that of the main tank, is more important than DPS output, it's probably prudent to fall back to the usual CoA or CoD. That said, raid planners should not overlook the DPS contribution of CoR. As a Warlock, always check with your raid leader if you're unsure of the nature of the encounter.
Examples of boss encounters where CoR is not recommended includes:
High King Maulgar
Later stages of Gruul
Essence of Suffering
In small group and soloing, CoR has the interesting (and fun) effect of negating fear effects. It can be used in tandem with CoS/CoE and Fear for the "fear yo-yo" maneuver.
Curse of Weakness
This widely underrated curse reduces the target's melee attack power by 350. Some raids are in fact stacking Curse of Weakness (CoW) and CoR to maximize their melee damage, especially if the tank in question is a Druid or Paladin.
AP-reducing effects do not stack, so stronger effects will overwrite weaker ones. Before including talents, the base AP debuffs are 350, 300 and 240 for the Warlock, Warrior and Druid respectively.
The maximum AP-reduction achievable by feral druids is 336, even with five points in Feral Aggression. On the other hand, warlocks with two points in Improved CoW can reduce AP by 420 - the biggest such effect in the game currently. Warriors match this with five points in Improved Demoralizing Shout. A 420AP reduction would just about negate the increased AP provided by CoR.
Reports have suggested that a mob's melee damage can be reduced by about 15% through AP-reduction.So, when do I use this?
With the new CoE, a second or third Warlock can be assigned to CoW duty on melee-based mobs in selected encounters if your group does not access to Improved Demoralizing Shout from a Warrior.
The use of CoW has to be balanced against the DPS needs of the encounter: is it a DPS race? Or is it a survival fight, where the main tank must survive? Given the number of warlocks in your raid, which debuffs are the most important and which ones are "good to have"?
Warlocks have also been discovering the damage mitigation power of CoW in small group content. The judicious use of this curse can mean the difference between a wipefest and a smoother run, especially in cases where your tank and/or healer is marginally geared.
Have you been using CoW often enough to note a difference? Is CoW the key to our PvP woes against rogues and warriors?
Curse of Tongues
This anti-caster curse is a great disruptor in PvP, slowing heals and forcing a curse removal in many cases. Curse of Tongues (CoT) is also key against casters and healers in some PvE encounters like Magtheridon and Fathom-Guard Caribdis. Unfortunately, many other caster mobs - particularly bosses - are immune to this curse.
So, when do I use this?
When your raid leader asks you to!
Having CoT up on certain mobs makes it easier for classes like rogues and shamans to interrupt casting. A debuff timer like ClassTimer is essential here, so that you can keep an eye on this 30-second curse while DPSing other targets.
Curse of Exhaustion
Another excellent PvP debuff; great against melee opponents that warlocks need to stay away from and flag runners in the battlegrounds. This curse is only available to affliction locks who spec for it, and is useful for kiting mobs like Vashj's striders. Curse of Exhaustion (CoEx) can also be used in tandem with CoR in managing mobs that are feared.
So, when do I use this?
This is the only slowing effect warlocks have. An enslaved Doomguard's Cripple ability doesn't really count; how often do you run with an enslaved Doomguard in PvP or PvE? Use it whenever you need to get out of a tough spot, or offensively to slow down targets running away from your awesomeness.
To summarize, CoS and CoE are useful must-haves for any encounter. The merging of CoS and CoE will free up a debuff slot and raids should consider including CoW and/or CoR, depending on raid composition and encounter nature. CoA and CoD are really the "fall-back" curses, used by warlocks who aren't assigned to any specific utility curse.
V'Ming finds Mount Hyjal a surreal experience: "I'm in an RTS!"