How do Aggro and Threat work in WoW
by Xardas | 15/01/2007 21:36:59
How do Aggro and Threat work in WoW
Originally created by: Kenco
Note: This article may not be fully updated as of patch 2.0.5. Please mention any errors you see in the article to keep it updated and correct.
1) Definitions: Threat vs Aggro, Threat Scale
We define "aggro" to be who the mob is attacking. A player has aggro, or pulls aggro, when the mob is attacking them. We define "threat" to be a numeric value that each mob has towards each player. Note that the target who has aggro is not necessarily the player with the highest threat.
To set a scale for threat, let 1 point of damage from a normal attack cause 1 point of threat, where the sense of normal will be clarified later. The threat values of some abilities are listed in the MPQs, and this 1:1 scale matches those abilities (e.g. feint, distracting shot, fade).
2) The Threat List
Imagine every mob as keeping a list of players and their threat values. If the mob is unaware of a player, that player will not be on the threat list. As soon as the mob becomes aware of a player, in the ways described below, they are put on the list with 0 threat. Knowing which players are on a mobs threat list and which mobs have a certain player on their threat lists is crucial in predicting a mobs behaviour.
A player can get on a mobs threat list in the following ways:
- Body Pulling, i.e. getting close enough to a mob that is out of combat.
- Body Pulling linked mobs. When you body pull a mob, youll also get onto the threat lists of all mobs that are linked to it. Note that after the pull they become unlinked; a second person attacking one of the mobs will only get on that mobs threat list after the pull.
- Buffing a player that is on the mobs threat list. That is, casting a healing spell or other buff spell.
- Direct damage or casting a debuff on the mob. Some debuffs, notably mind vision and hunters mark, wont put you on the mobs threat list.
- Bosses in-combat pulse. For most high level instance bosses, every tick (2 seconds) every player in the instance is added to the boss threat list when the boss is in combat.
- In combat proximity. Many mobs with secondary targeting or AOE abilities will add nearby players to their threat lists. For other mobs, as long as they are in combat you can stand on top of them and not get added to their threat list.
3) Aggro Transfer, Threat Decay
To prevent mobs rapidly swapping targets when many players have similar threat, a mob will stay on its current target unless another player has significantly higher threat. Suppose a mob has aggro on a certain player X. Then to pull aggro while in melee range, another player needs 110% of Xs threat. If the other player is outside melee range, they need 130% of Xs threat to pull aggro. This means than in general, once you have aggro it is easy to keep it, and once you lose aggro it is hard to regain it. It also stops two players attacking a mob from range and constantly swapping aggro between them, because as their threat increases, the 30% margin will be harder and harder to overcome.
Note that the 10% effect is determined only by your range, not the ability used. If you are generating threat from healing or a range ability such as Frostbolt, you will still pull aggro at 110% if you are within melee range of the mob.
In the normal course of events, threat does not decay. Once you are on a mobs threat list, youre there until its dead or you are, and your threat does not decay over time. There are of course mobs with specific abilities that reduce threat, and player abilities also, which do decrease your threat.
4) AoE Threat: Healing, Buffing, Power Gain
Each point of healing causes 0.5 threat, forgetting threat modifiers. Overhealing doesn't cause threat. Most buff spells cast on friendly players generate a small amount of threat. Gaining Power (Mana / Energy / Rage) also causes threat in most cases, for example taking a healing potion, or gaining rage from Bloodrage, or Energy from Thistle Tea. Certain spells are exempt, for example mana from Blessing of Wisdom or a Mana Spring totem doesnt cause threat, and there is no threat from the healing gained from Siphon Life. For normal abilities, each point of Mana is 0.5 threat, Rage is 5 threat, and Energy is unknown, probably 5. In the scheme of things, threat from power gain is usually irrelevant, unless you have consistent or burst values, such as taking a mana potion or having Fel Energy running.
These forms of buffs all have infinite range; they will cause threat to all mobs on whose threat list you are on. Furthermore, the threat caused is split equally among all the affected mobs. If you are on one mobs threat list, a 1000 point heal will cause 500 threat to that mob. If 5 mobs are aware of you, the same heal will cause 100 threat on each mob.
Note that threat caused from Power Gain is not affected by threat modifiers. Gaining 1 point of Rage will give 5 threat whether you are in Battle Stance or Defensive Stance.
5) Threat Modifiers: Common Modifiers, Interaction
Here are some of the more common threat modifiers and their values, assuming you have the maximum number of talent points in the talents mentioned:
Warrior in Defensive Stance / Druid in Bear Stance: x1.3
Warriors 5/5 Defiance / Druids 5/5 Feral Instinct: x1.15 (in above stances only)
Warrior in Battle or Berserker Stance: x0.8
Rogue (passive, always on): x0.71
Blessing of Salvation: x0.7
Tranquil Air Totem: x0.8
Priests 5/5 Silent Resolve: x0.8 (spells)
Mages 3/3 Frost Channelling: x0.9 (frost spells)
Mages 3/3 Burning Soul: x0.9 (fire spells)
Mages 2/2 Arcane Subtlety: x0.6 (arcane spells)
As of 1.12, all threat modifiers are multiplicative, which makes them independent. Blessing of Salvation "reduces your threat by 30%", which is implemented as "multiplies your threat by 70%". Two different modifiers just multiply on each other, so Blessing of Salvation + Arcanist 8/8 + Frost Channeling would be 0.7 x 0.85 x 0.9 = 53.55% threat. The primary effect of the 1.12 change is to stop several threat modifiers combining too powerfully; for example it was possible to achieve 0% threat generation using the Fetish of the Sand Reaver.
It is useful to consider the inverse multiplier, which is the increase in damage or healing potential as a result of a threat modifier. Suppose you have Blessing of Salvation on, for a 0.7 threat modifier. Then to get 1 point of threat, you can now do 1 / 0.7 = 1.43 points of damage. In other words, the Blessing of Salvation buff allows you to do 43% more damage for the same threat. Similarly, the Rogue passive modifier allows you to do 40.8% more damage for 1 threat. To combine them, just multiply 1.43 * 1.408 = 101% more damage for 1 point of threat, compared to a player with no threat modifiers.
Most warrior abilities add a fixed amount of threat when they land successfully. The following table gives the raw values, i.e. before the modifiers from battle stance or defensive stance, and ignores the damage done by the abilities.
Heroic Strike 8...........145
Heroic Strike 9 (AQ)....173
Revenge 6 (AQ)..........355
Shield Slam (1.11)......250
While best used at 5 applications of Sunder, it generally provides a modified threat level equivalent to Sunder Armor around 2 applications of Sunder, depending on weapon and gear. (thanks to Lavina)
Damage scales per Sunder Armor.
Battle Shout generates 55 threat for each player that is buffed; up to 5 people in your party and their pets, as long as they are on the relevant mob's threat list. For example if you buff a player that is out of combat, no threat is generated. Therefore in a tightly packed group, Battle Shout can rival Sunder Armor for threat, but as a buff the threat is split amongst all the mobs that are aware of you. On the other hand, Demoralizing Shout gives 43 threat to each affected mob. As long as there are 6 or more mobs affected, it will hold aggro as well or better than Sunder Armor.
From the 2.0 PTR patch notes: "Fixed an issue where Warrior "Battle Shout" was causing too much threat." - it is expected that "battleshout tanking" will no longer be effective and that the threat value of the shout is significantly reduced, though it's not clear yet how this has been changed.
Taunt does 3 things:
- Taunt debuff. The mob is forced to attack you for 3 seconds. Later taunts by other players override this.
- You are given threat equal to the mob's previous aggro target, permanently. Importantly, you won't necessarily get as much threat as the highest person on the mob's list, only as much as whoever is currently tanking it.
- You gain complete aggro on the mob at the instant you taunt. Usually you would need 10% more threat to gain aggro (see section 3), but a taunt now gives you instant aggro on the mob. Of course if other people are generating significant threat on the mob, they could exceed your threat by more than 10% before the taunt debuff wears off, and will gain aggro as soon as it does. There is no limit to the amount of threat you can gain from Taunt.
While Challenging Shout and Mocking Blow have a similar forced attack debuff to Taunt, they do not give the caster threat in the same way as Taunt, just fixed amounts.
Growl (Druid) and Righteous Defense (Paladin) behave the same way as Taunt.
[ Post edited by Xardas ]
Bumped: BlizzCon 2010 Schedule Announced