A debuff is the inverse of a buff. It is an effect that hampers the target in some way for a duration. Among other effects, debuffs usually lower attributes, hinder the effectiveness of the target's actions, or cause damage over time.

Similarly with buff, certain debuff are stackable: repeated application on the same target will causes a stacking effect of increased effectiveness. Non-stackable debuffwill only be refreshed by repeated application. All debuffs are temporary, and will not persist after the affected target's death.

There are currently 3 sources of debuffs: champion abilities, summoner spells, and item active effects.

Champion Abilities[编辑 | 编辑源代码]

Majority of the champions possesses a certain type of debuff. Such debuff can be armor reduction from Wukong's Wukong's Crushing Blow Crushing Blow, magic resist reduction from Fiddlesticks' Fiddlesticks' Dread Dread, or attack damage reduction from Trundle's Trundle's Rabid Bite Rabid Bite.

A debuff that reveals its victim to the enemies may cause other wards and stealthed units near the victim to be reveal as well. Currently Nidalee's Nidalee's Bushwhack Bushwhack and Caitlyn's Caitlyn's Yordle Snap Trap Yordle Snap Trap works 100% of the time. Corki's Corki's Phosphorous Bomb Phosphorous Bomb and Lulu's Lulu's Help, Pix! Help, Pix! have unconfirmed effects for the first, while the latter being less consistent.

Damage over time, and Direct CC such as Amumu's Amumu's Bandage Toss Bandage Toss will not be included. Crowd control, which is also a form of debuff by default and covered by crowd control section.

Champion Ability Effect Duration Notes
Akali Akali Mark of the Assassin Mark of the Assassin Deals damage and restores Akali's Akali's energy when consumed 6 seconds N/A
Amumu Amumu Cursed Touch Cursed Touch Reduces magic resist by 15/25/35 when autoattacked by Amumu Amumu 3 seconds N/A
Anivia Anivia Rebirth Rebirth Reduces Anivia's armor and magic resist by 40/25/10 during her Rebirth 6 seconds Gains armor and magic resist instead at higher levels
Flash Frost Flash Frost
Glacial Storm Glacial Storm
Enemies affected by these abilities are slowed and take increased damage from Frostbite Frostbite 6 seconds
Brand Brand Blaze Blaze Enemies affected suffer additional effects from Brand's Brand's abilities and receive magic damage equal to 2% of their maximum health over 4 seconds 4 seconds Every one of Brand's Brand's abilities apply this debuff.
Caitlyn Caitlyn Yordle Snap Trap Yordle Snap Trap Enemy champions who activate this trap are revealed for 9 seconds, take magic damage and are snared for 1.5 seconds. 9 seconds Only champions can activate the trap.
Cassiopeia Cassiopeia Noxious Blast Noxious Blast
Miasma Miasma
Enemies affected are poisoned, taking Damage over time and reducing the cooldown of Twin Fang Twin Fang to 0.5 seconds when targetted. 2-3 seconds
Corki Corki Phosphorus Bomb Phosphorus Bomb Enemies hit will take magic damage and revealed for a duration. 6 seconds N/A
Gatling Gun Gatling Gun Enemies within the area will take physical damage and receive a armor debuff of 1/2/3/4/5 per half a second for up to 4 seconds. 2 seconds Stacks up to 9 stacks
Darius Darius Hemorrhage Hemorrhage Applies a stacking DoT on autoattacks and skills. Enhances certain abilities. 5 seconds Stacks 5 times. Reduces cooldown of Crippling Strike Crippling Strike by 1 second per stack on target. Increases damage done by Noxian Guillotine Noxian Guillotine per stack.
Diana Diana Crescent Strike Crescent Strike Reveals targets afflicted with Moonlight and Lunar Rush's Lunar Rush's cooldown is refreshed if used on target. 3 second All active Moonlight debuffs are consumed when Lunar Rush Lunar Rush is casted.
Draven Draven Wicked Blades Wicked Blades Spinning Axe Spinning Axe Critical Strikes and Spinning Axe Spinning Axe apply a physical DoT. 4 seconds
Fiddlesticks Fiddlesticks Dread Dread Nearby enemy units have their magic resist reduced by 10.
Fizz Fizz Seastone Trident Seastone Trident Upon activation, deal bonus magic damage on hit and inflicts Grievous Wounds for a duration. 5 seconds
Chum the Waters Chum the Waters Enemies affected are slowed and a shark will deal magic damage and knock them in the air, along with all surrounding enemies when the debuff expires. Up to 1.5 seconds
Gragas Gragas Barrel Roll Barrel Roll Enemies who are dealt magic damage will also receive an attack speed debuff of 20/25/30/35/40 % 3 seconds N/A
Graves Graves Smokescreen Smokescreen Deals magic damage to enemies in the area, and creates a smokescreen which reduces enemy sight range by 625 range within the affected area as long as they stay within the area. 4 seconds N/A
Heimerdinger Heimerdinger H-28G Evolution Turret H-28G Evolution Turret From Rank 2 onwards, Turret's damage will apply an armor and magic resist reduction of 1 per stack. 2 seconds Stacks up to 50 stacks
Jarvan IV Jarvan IV Dragon Strike Dragon Strike Deals physical damage to enemies in a line, and apply an armor debuff which reduces armor by 10/14/18/22/26 % for a duration. 3 seconds
Karthus Karthus Wall of Pain Wall of Pain Any enemy who passes through the wall suffer reduced Magic Resistance by 15% and are slowed by 40/50/60/70/80% 5 seconds
Kassadin Kassadin Riftwalk Riftwalk Upon casting Riftwalk, additional casts within a period cost 100 more mana up to a maximum of 1000 additional mana. 8 seconds Riftwalk damage is also increased.
Katarina Katarina Bouncing Blade Bouncing Blade Deals damage when consumed 5 seconds
Death Lotus Death Lotus Applies Grievous Wounds on hit.
Kayle Kayle Holy Fervor Holy Fervor Every autoattack will apply a debuff that reduces target's armor and magic resist by 3%. 5 seconds Stacks up to 5 stacks.
Reckoning Reckoning Blast a target with magic damage, slowing it and increases the damage that target receive from Kayle by 6/7/8/9/10 %. 4 seconds Debuff also slows for 35% at all level.
Kennen Kennen Mark of the Storm Mark of the Storm Stuns affected enemies for 1 second and restores Kennen's Kennen's energy by 25 upon reaching 3 stacks. Stun duration is halved if applied more than once in a 7 second period. 8 seconds
Kog'Maw Kog'Maw Caustic Spittle Caustic Spittle Kog'Maw launches a corrosive projectile at a single target which deals magic damage and reduces its armor and magic resist by 5/10/15/20/25 and also leaves a trail behind the person that's hit. 4 seconds N/A
Living Artillery Living Artillery Upon casting Living Artillery, additional casts of Living Artillery will cost 40 additional mana per stack up to a maximum of 200 additional mana 4 seconds N/A
LeBlanc LeBlanc Sigil of Silence Sigil of Silence Deals magic damage and marks the target. If LeBlanc LeBlanc damages them with another spell, they will take additional magic damage and be silenced for 2 seconds. 3.5 seconds
Ethereal Chains Ethereal Chains Deals magic damage and tethers an enemy, slowing their movements. If they remain in the tether for 2 seconds, they take additional magic damage and be snared for 1/1.3/1.6/1.9/2.2 seconds 2 seconds
Lee Sin Lee Sin Sonic Wave Sonic Wave Deals magic damage to a target and reveals them. Enemies affected by this debuff will be targetted by Resonating Strike Resonating Strike when activated. 3 seconds
Tempest Tempest Deals magic damage to all nearby enemies and reveals them. Enemies affected by this debuff will also be affected by Cripple Cripple when activated. 4 seconds
Cripple Cripple Cripples all enemies revealed by Tempest Tempest reducing their movement and attack speed. The movement and attack speed recover over 4 seconds. 4 seconds Effect will only apply to those marked by Tempest Tempest.
Leona Leona Sunlight Sunlight When Leona's Leona's allies deal any damage to targets with Sunlight, they consume the Sunlight debuff to deal additional 20/35/50/65/80/95/110/125/140 magic damage. 3.5 seconds Applied by all of Leona's Leona's spells.
Lux Lux Illumination Illumination When autoattacked by Lux Lux or hit by Finales Funkeln Finales Funkeln, she consumes the Illumination debuff to deal additional 10 + (10xlevel) magic damage. 3.5 seconds Applied by all of Lux's Lux's damaging spells, including Finales Funkeln Finales Funkeln (after consumed).
Malphite Malphite Ground Slam Ground Slam Reduces attack speed of all enemies hit by 30/35/40/45/50% 3 seconds N/A
Malzahar Malzahar Malefic Visions Malefic Visions If the target dies with this debuff, Malefic Visions Malefic Visions will affect another nearby unit while restoring 10/14/18/22/26 mana to Malzahar Malzahar. 4 seconds Duration is refreshed when it affects another target.
Miss Fortune Miss Fortune Impure Shots Impure Shots Healing effects and health regeneration on this target are halved for the duration of the debuff. 3 seconds N/A
Mordekaiser Mordekaiser Children of the Grave Children of the Grave If the target dies while under the effect of the curse, their soul is enslaved and will follow Mordekaiser for 30 seconds. 10 seconds Mordekaiser heals himself for the damage dealt by this ability.
Morgana Morgana Tormented Soil Tormented Soil Enemy units who stand on Tormented Soil lose magic resistance 4/5/6/7/8 every second they are standing on the area. Stacks up to 5 times, also refreshing the duration.
Soul Shackles Soul Shackles Enemy units who stay tethered for 3 seconds are then dealt magic damage and are stunned for 1.5 seconds 3 seconds During the duration of the debuff, targets are slowed by 20%.
Nasus Nasus Wither Wither Nasus Nasus ages his target, slowing their movement and attack speed by 35%. Additionally, they are reduced further to reach an extra 12/24/36/48/60% slow. 5 seconds If the duration is reduced by Tenacity, the extra slow will be applied faster for it to reach its maximum at the end of the duration.
Spirit Fire Spirit Fire Enemy units who stand on Spirit Fire lose 20/25/30/35/40 Armor. 1 seconds Staying in Spirit Fire will continually refresh the debuff
Nautilus Nautilus Depth Charge Depth Charge Depth Charge will travel between Nautilus and this target, dealing damage and knocking up all units in its path. When Depth Charge reaches the target, it consumes the debuff, dealing damage, knocking up the target and stunning for 1/1.5/2 seconds Varies Depth Charge will accelerate as it travels.
Nidalee Nidalee Bushwhack Bushwhack Bushwack reveals enemies who trigger it and reduces their armor and magic resistance by 20/25/30/35/40%. 12 seconds N/A
Nocturne Nocturne Duskbringer Duskbringer Targets leave a Dusk Trail along their paths, revealing their movements. While on this Dusk Trail, Nocturne Nocturne ignores unit collision and gains 15/20/25/30/35% Movement Speed and 15/25/35/45/55 Attack Damage. 5 seconds
Unspeakable Horror Unspeakable Horror Tethers nearby enemies to Nocturne. If they remain tethered for the duration of the debuff, they will be Feared for 1/1.25/1.5/1.75/2 seconds 2 seconds
Paranoia Paranoia Reduces the sight radius of all enemy champions by 300 and removes their ally vision; this includes champions, minions, wards, towers, and clairvoyance. 4 seconds
Nunu Nunu Ice Blast Ice Blast Ice Blast slows targets movement speed by a percentage and attack speed by 25%. 3 seconds N/A
Absolute Zero Absolute Zero Enemies in Absolute Zero's area while it is being channeled are slowed by 50% and have their attack speed reduced by 25%. 0.5 seconds Staying in the zone will refresh the debuff up to 3 seconds. It can be canceled early.
Poppy Poppy Diplomatic Immunity Diplomatic Immunity Debuffed enemies take 20/30/40% increased damage from Poppy Poppy. 6 / 7 / 8 seconds For the duration of the debuff, Poppy Poppy can only be damaged by debuffed units. This effect ends prematurely if the target dies. Cleansing this debuff will make Poppy Poppy invulnerable for the duration.
Rammus Rammus Puncturing Taunt Puncturing Taunt Taunts a target enemy, reducing their armor by 10/15/20/25/30 and forcing them to attack Rammus for a few seconds. 1/1.5/2/2.5/3 seconds N/A
Renekton Renekton Slice and Dice Slice and Dice Reduces armor of all enemies hit by Dice Dice by 15/17.5/20/22.5/25% 4 seconds Only when empowered by Fury.
Ryze Ryze Spell Flux Spell Flux Reduces the targets' magic resistance by 12/15/18/21/24 per hit. 5 seconds N/A
Sejuani Sejuani Frost Frost Slows enemies by 10% and will be targetted by Permafrost Permafrost when activated 3 seconds Applied through autoattacks, Arctic Assault Arctic Assault and Glacial Prison Glacial Prison
Shaco Shaco Two-Shiv Poison Two-Shiv Poison Non-champion units affected have a 20/22.5/25/27.5/30% chance to miss their autoattacks 2 seconds N/A
Shen Shen Vorpal Blade Vorpal Blade Throws a sword at an enemy, dealing magic damage. The enemy is life-tapped; allied champions that damage a life-tapped enemy are healed over 3 seconds, with the duration refreshed upon subsequent damaging. 5 seconds N/A
Shyvana Shyvana Flame Breath Flame Breath Enemies hit by the fireball have their armor reduced by 15% and take further magic damage equal to 15% of the ability damage when struck by Shyvana's autoattacks. 4 seconds
Singed Singed Poison Trail Poison Trail Poisons enemies, dealing damage over time and reducing the cooldown of Twin Fang Twin Fang to 0.5 seconds if hit by it. 3 seconds Continual exposure renews the poison.
Skarner Skarner Fracture Fracture If Skarner attacks enemies hit by Fracture, he restores health. The heal becomes less potent with every mark he consumes. 6 seconds N/A
Sona Sona Power Chord Power Chord If Aria of Perseverance Aria of Perseverance was cast last prior to using Power Chord Power Chord, the target deals 20% reduced damage. 4 seconds N/A
Soraka Soraka Starcall Starcall Reduces the targets' magic resistance by 8/9/10/11/12. This effect stacks up to 10 times. 5 seconds N/A
Swain Swain Torment Torment Deals magic damage over time and causes any further damage dealt by Swain during this period to be increased by 8/11/14/17/20%. 4 seconds N/A
Talon Talon Noxian Diplomacy Noxian Diplomacy Deals physical damage over time and reveals the marked champion 6 seconds Only affects Champions
Cutthroat Cutthroat Silences enemy champion for 1 second and causes any further damage dealt by Talon to be amplified by 3/6/9/12/15% 3 seconds Only affects Champions
Taric Taric Shatter Shatter Reduces the armor of enemies hit by 10/15/20/25/30 4 seconds N/A
Teemo Teemo Toxic Shot Toxic Shot
Noxious Trap Noxious Trap
Poisons all enemies hit, dealing damage over time and reducing the cooldown of Twin Fang Twin Fang to 0.5 seconds if targetted 4 seconds N/A
Tristana Tristana Explosive Shot Explosive Shot Deals magic damage over time and reduces the potency of healing effects and health regeneration on the target by 50% 5 seconds N/A
Trundle Trundle Rabid Bite Rabid Bite Reduces the target's Attack Damage by 10/12.5/15/17.5/20 8 seconds Trundle gains double the Attack Damage reduction in bonus Attack Damage for the same duration.
Agony Agony Deals magic damage over time and reduces target's Armor and Magic Resist by 15/20/25%. Armor and Magic Resist reduction doubles over the duration of the debuff. 6 seconds Trundle heals for the damage dealt and receives bonus Armor and Magic Resist equal to the amount reduced.
Tryndamere Tryndamere Mocking Shout Mocking Shout Reduces the target's Attack Damage by 20/35/50/65/80 4 seconds Also slows enemies who are not facing Tryndamere by 30/37.5/45/52.5/60%.
Twisted Fate Twisted Fate Destiny Destiny Reveals position to the enemy team, including champions in stealth. 6/8/10 seconds
Twitch Twitch Deadly Venom Deadly Venom Deals damage over time, and when Expunge Expunge is activated, it deals additional damage per stack. 6 seconds May stack up to 6 times.
Urgot Urgot Zaun-Touched Bolt Augmenter Zaun-Touched Bolt Augmenter Reduces damage dealt by affected units by 15% 2.5 seconds Applied by Urgot's autoattacks and Acid Hunter Acid Hunter
Noxian Corrosive Charge Noxian Corrosive Charge Reduces armor of affected units by 12/14/16/18/20% and allows lock-on targetting with Acid Hunter Acid Hunter 5 seconds
Vayne Vayne Silver Bolts Silver Bolts At three stacks, Silver Bolts is consumed to deal true damage based off the target's maximum health 3 seconds Applied by Vayne's autoattacks and Condemn Condemn. Stacks are lost upon switching targets.
Viktor Viktor Gravity Field Gravity Field Slows enemies 28/32/36/40/44% while building stacks for every 0.5 seconds they remain in the field. At three stacks, targets are stunned for 1.5 seconds.
Vladimir Vladimir Tides of Blood Tides of Blood Upon casting Tides of Blood, Vladimir gains an empowered stack, increasing the health cost of Tides of Blood by 25%, stacking up to 4 times to a maximum of twice the listed health cost. 10 seconds Self-healing and Regeneration is increased by 4/5/6/7/8% per stack and Tides of Blood base damage is increased by 25%
Hemoplague Hemoplague Affected enemies take 12% amplified damage from all sources. At the end of the debuff, they take magic damage. 5 seconds
Warwick Warwick Eternal Thirst Eternal Thirst Takes additional magic damage from Warwick's autoattacks, while healing him for the same amount. This effect stacks up to 3 times. 4 seconds
Blood Scent Blood Scent Reveals location to enemy team while hasting Warwick by 20/25/30/35/40% Constantly reapplied when at less than 50% health and within 1,500/2,300/3,100/3,900/4,700 distance units of Warwick.
Wukong Wukong Crushing Blow Crushing Blow Reduces armor of enemies hit by 30% 3 seconds
Xin Zhao Xin Zhao Challenge Challenge Reducing armor by 15% when Xin Zhao lands basic attacks or Audacious Charge. 3 seconds Only one target can be challenged at a given time. Affected unit is unaffected by the knockback of Crescent Sweep Crescent Sweep.
Xerath Xerath Mage Chains Mage Chains If hit by another one of Xerath's spells, the target is stunned by 1.5 seconds 3 seconds
Zilean Zilean Time Bomb Time Bomb At the end of this debuff, targetted enemies take magic damage. The target will take 3, 2, 1 additional true damage per second as it counts down. 4 seconds Applying a second Time Bomb Time Bomb before the first has finished counting down will detonate the first bomb prematurely, while refreshing the duration.

Summoner Spells[编辑 | 编辑源代码]

Summoner spells have greater effect as a debuff as compared to champion abilities.

  • Exhaust reduces the damage dealt from the affected champion and slow it greatly.
  • Ignite deals true damage over 5 seconds, and reducing all healing and regeneration effects on the affected target for the duration.

Item Effects[编辑 | 编辑源代码]

Certain items possesses capability to debuff enemy. Some of it will not debuff enemy unless the active component was utilized, some will automatically do so when certain action was fulfilled (such as autoattack, casting spells etc), and some may possesses both components.

Active Items[编辑 | 编辑源代码]

These items does not have a passive effect of debuffing enemy on its own, but possesses an active component that will debuff enemy.

  • Bilgewater Cutlass Bilgewater Cutlass active effect will deal magic damage and slow its target's movement speed by 50% for 3 seconds.
  • Hextech Gunblade Hextech Gunblade active effect will deal magic damage and slow its target's movement speed by 50% for 3 seconds.

Passive Item[编辑 | 编辑源代码]

Items such as the following will debuffs enemies automatically when they comes into range. No activation is required to bring the effect into place.

  • Abyssal Scepter Abyssal Scepter passively reduces all nearby enemy champions' magic resist by 20.
  • Frozen Heart Frozen Heart passively slows all nearby enemies' attack speed by 20%.
  • Frozen Mallet Frozen Mallet passively allows auto-attacks to slow your target's Movement Speed by 40% for 2.5 seconds. (30% for ranged attacks)
  • Malady Malady inflict 20 magic damage on-hit and reduces the target's magic resistance by 6 for 8 seconds. Stacks up to 4 times.
  • Phage Phage gives auto-attacks 25% chance to slow the target's Movement Speed by 30% for 2.5 seconds.
  • Rylai's Crystal Scepter Rylai's Crystal Scepter passively causes your spell damage to additionally slows the target by 15% or 35% for 1.5 seconds.
  • The Black Cleaver The Black Cleaver allow auto-attacks to reduce your target's armor by 15 for 5 seconds. Stacks up to 3 times.
  • Trinity Force Trinity Force allows auto-attacks to have a 25% chance to slow your target's movement speed by 35% for 2.5 seconds.
  • Warden's Mail Warden's Mail causes user to have 20% chance on being hit by an auto-attack to reduce attacker's movement speed and attack speed by 35% for 3 seconds.

Items with both components[编辑 | 编辑源代码]

These are items with both a passive and active component that both debuffs the enemy.

  • Executioner's Calling Executioner's Calling inflict 4 damage per second on-hit for 8 seconds. Upon activation, auto-attacks temporarily apply Grievous Wound which reduces healing and regeneration effects by 50% for 8 seconds.
  • Randuin's Omen Randuin's Omen grants the wielder 20% chance on being hit by an auto attack to slow the attacker's movement and attack speed by 35% for 3 seconds. Upon activation of its active component, it will slows movement speed and attack speed of surrounding enemy units by 35% for 2 seconds + 0.5 seconds for every 100 armor and magic resistance.