Diminishing returns, abbreviated DR,[1] means that certain spells and abilities are less effective against player characters if they are used frequently within a short period of time. The table below contains a list of abilities that are affected by DR, and under what circumstances. In addition, DR categories are listed. Effects within same category diminish each other.
When a spell with diminishing returns is used against a target in PvP, the first effect has full duration. The effect then diminishes by 50%, then 75%, then the target becomes immune. Spells must be used on the same target within 15 seconds of the *end* of the duration in order to be diminished. In other words, if a target hasn't had a stun effect active on them for more than 15 seconds, the next stun will have full effect.
Some abilities share diminishing returns—that is, it doesn't matter which one you use; the next time you use an ability in the same category on the same target, its duration will be diminished just as if you had used the exact same ability. These abilities fall into the same category.
It should be noted that the server does not reset diminishing returns after exactly 15 seconds. Instead, it checks every 5 seconds if there are any diminishing returns that should be reset because the last spell in their category was cast on the target more than 15 seconds ago. As a result, a particular diminishing return category may take anywhere between 15 and 20 seconds to reset. Most addons guess that a DR category has reset after 18 seconds by default.
Fear - Blind, Fear (Warlock), Howl of Terror, Intimidating Shout, Psychic Scream, Scare Beast, Seduction (Pet), Turn Evil
Horror - Death Coil, Psychic Horror
Opener Stun - Cheap Shot, Pounce
Random Root - Improved Cone of Cold, Improved Hamstring, Shattered Barrier
Random Stun - Impact, Seal of Justice, Stoneclaw Stun
Silence - Arcane Torrent, Gag Order (Warrior talent), Garrote, Improved Counterspell, Nether Shock, Silencing Shot, Improved Kick, Shield of the Templar, Silence (Priest), Spell Lock, Strangulate
Taunt - Angered Earth, Challenging Howl, Challenging Roar, Challenging Shout, Dark Command, Death Grip, Distracting Shot, Growl (Druid), Hand of Reckoning, Mocking Blow, Righteous Defense, Taunt (Pet),Taunt (Warrior)
Scatter - Scatter Shot, Dragon's Breath
Banish, Charge, Cyclone, Entrapment, and Mind Control are on diminishing returns with themselves.
Diminishing Returns in PvE
Many types of crowd control also suffer from diminishing returns versus NPCs. Diminishing returns do not count per player but per creature; every creature has its own diminishing return for each group of CC and all players in your party / raid will be affected by that diminishing return.
Patch changes
Patch 3.3.0 (08-Dec-2009): Taunt Diminishing Returns: We've revised the system for diminishing returns on Taunt so that creatures do not become immune to Taunt until after 5 Taunts have landed. The duration of the Taunt effect will be reduced by 35% instead of 50% for each taunt landed. In addition, most creatures in the world will not be affected by Taunt diminishing returns at all. Creatures will only have Taunt diminishing returns if they have been specifically flagged for that behavior based on the design of a given encounter.
Hotfix (2009-09-09): "We just deployed a hotfix to modify [Holy Wrath] so this spell has the same diminishing return mechanics that other player stun spells and abilities currently have. This will prevent Undead creatures that we wish to be susceptible to stun from being permanently stunned if you include enough Paladins in your raid who then rotate their Holy Wrath casts.
This will affect the difficulty of Anub'arak, but we didn't want the "right way" to defeat this fight to involve bringing five Paladins who [glyphed] their Holy Wrath spell."
Hotfix (2009-04-30): "Blind (Rogue) is now in the same diminishing returns category as Fear effects, but no longer shares diminishing returns with [Cyclone] (Druid)."
[Blind] is now a physical (no longer a poison) attack. Reagent requirement removed. Now shares the same diminish category as [Cyclone] and is now diminished in PvE as well as PvP.
[Riposte] is now subject to diminishing returns in PvP.
[Frost Shock] is no longer subject to diminishing returns.
[Unstable Affliction]: The silence from this ability is now subject to diminishing returns.
[Disarm] is now subject to diminishing returns in PvP.
Patch 1.4.0 (2005-05-05): A handful of spells were added to the list of spells subject to diminishing returns in PvP. It is our goal to set as few spells as possible to be diminished. We've identified this short list of spells as having durations and cooldowns sufficient to almost permanently slow or immobilize targets but without adequate controls or other limiting factors. When a spell with diminishing returns is used against a target in PvP, the first effect has full duration. On the second use of the same category of spell (e.g. slowing), that spell's duration is reduced by 50%. On the third use, the duration is reduced by 75%. On the fourth attempt, the target becomes immune to the spell. Spells must be used on the same target within 15 seconds of the *end* of the duration in order to be diminished. In other words, if a target hasn't had a slowing spell active on them for more than 15 seconds, the next slowing spell will have full effect. The list of affected spells is: