Crowd control



Crowd control (commonly shortened to CC) is a blanket term used in League of Legends to describe abilities or spells that remove or diminish the control a target unit has over aspects of itself - aspects such as being able to cast spells or initiate movement commands. As crowd controls impact a unit's combat ability, they are essentially more specialized forms of debuffs - however, this ability to directly hinder a unit's ability to fight means that crowd controls are often given significantly more importance in regular gameplay than normal debuffs, resulting in their special classification.

There are many different forms of crowd control, each of which is unique in the way it affects its target and the ways it can - if at all - be resisted, mitigated or removed. Some crowd controls can be exclusive or near-exclusive to certain champions or items, and different champions can apply the same crowd control in multiple different ways. A few specific mechanics (such as ) even require a catalyst crowd control to function.

All crowd controls, at the exception of, , or , even the ones without any damage, will count toward assists.

Types of Crowd Control
Descriptive=
 * For the complete article, see Types of Crowd Control.

The following are the current forms of crowd control that exist within League of Legends:

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 * : A unit that is airborne is unable to control its movement, attack or cast abilities for the duration.
 * Knock aside: A knock aside causes the target to be made airborne in a direction perpendicular to the direction of cast.
 * Knockback: A knockback causes the target to be made airborne in a direction away from the point of cast. The duration depends on how far the target travels, from seconds  to.
 * Knockup: A knockup causes the target to be made airborne on the spot. The duration depends on how high is the target thrown into the air, from seconds  to.
 * Pull: A pull effect causes the target to be made airborne in a direction toward the point of cast.
 * : A unit that is blind will miss its auto-attacks for the duration. Miss occurs on-hit, and does not prevent attacks from being declared.
 * : A unit that is disarmed cannot declare attacks for the duration.
 * is a combination of Disarm and Root.
 * is a combination of Disarm and Silence (aka Pacify). The only example also reduces movement speed for the duration.
 * Forced Action: A unit that is under the effect of a forced action cannot control its own movement or attacks, and is unable to cast abilities.
 * : A unit that is charmed will move toward the source for the duration.
 * : A unit that is feared move around randomly at reduced movement speed for the duration. There are currently no examples of Fear that affect champions.
 * : A unit that is fleeing will move directly away from the source with reduced movement speed for the duration.
 * : A unit that is taunted will attempt to basic attack the source of the taunt for the duration.
 * : A unit that is grounded is unable to activate mobility spells.
 * : A unit that is knocked down is placed on the ground.
 * : A unit that is nearsighted has their sight radius reduced by 900 and loses their allied vision.
 * : A unit that is rooted is unable to control its movement for the duration (occasionally referred to as a snare).
 * : A unit that is silenced cannot cast abilities or activate items for the duration.
 * : A unit that has fallen asleep is unable to move, attack or cast abilities for the duration as long as it doesn't get damaged.
 * : A unit that is slowed has reduced movement speed for the duration.
 * : A unit that is crippled has reduced attack speed for the duration.
 * : A unit that is in stasis is unable to perform any action while being untargetable and invulnerable. The duration is also unaffected by crowd control reduction.
 * : A unit that is stunned is unable to move, attack or cast abilities for the duration.
 * : A unit affected by suspension can be targeted by, but is otherwise identical to a stun.
 * : A unit that is suppressed is unable to control its movement, attack, cast abilities or use spells (including ). The duration is also unaffected by crowd control reduction.

Categorization
To facilitate easier communications, crowd controls are usually described under one of the following systems:

Loss of Control
Crowd controls are grouped into one of two categories depending on whether or not the effect removes total control of the player's character. Hard CC completely removes all control of a character, while soft CC only partially removes it.



Disruption
Crowd controls are grouped into one of two categories depending on whether or not the effect disrupts a channeled ability (such as and ). Hard CC will disrupt all channels, while soft CC will not.



Immobilization
Crowd controls are grouped into one of two categories depending on whether or not they restrict movement. Hard CCs prevent all forms of movement, while soft CCs do not.



Modifiers
Crowd controls are categorized by what their effects inhibit. Movement modifiers in some way inhibit the ability to move, while action modifiers in some way inhibit the ability to attack or cast abilities.



Increasing the duration of Crowd Control
 is a status effect that can be applied by and. Enemies can have up to 2 marks of .

Each mark reduces the target's tenacity by 30% or in other words, increases the duration of incoming Crowd Control by 30% (including effects).

Countering Crowd Control
Crowd control can be countered in various different ways.

Immunity
Units that are immune to crowd control will completely negate any attempt at its application on the recipient. This does not, however, necessarily mean the user is now also unaffected by crowd controls already applied.

All forms of crowd control currently in League of Legends can be prevented with CC immunity.


 * provides immunity to CC applied with first instance of ability blocked while passive is ready.
 * provides immunity to CC applied with first instance of ability blocked in the duration.
 * provides immunity to all forms of CC applied during the parry.
 * (as )'s provides immunity to all slows while active.
 * provides immunity to all forms of CC applied in the duration.
 * provides immunity to all slows applied in the duration.
 * provides immunity to all forms of CC applied in the duration of the shield.
 * provides immunity to CC applied with first instance of ability blocked in the duration.
 * provides immunity to all forms of CC applied in the duration, with exception of nearsight.
 * provides immunity to all slows while active.
 * provides immunity to CC applied with first instance of ability blocked in the duration.
 * provides immunity to all forms of CC.

While not specific to crowd control, spell shields can be considered to provide pseudo-CC immunity against a single spell, but this is not guaranteed - abilities that do not interact with spell shields (such as ) will still apply any attached crowd controls if possible.

Deferral
Similar to immunity, abilities that defer crowd control will negate their effects while the ability is active, but any CC still present will be applied after the duration ends. CC duration will still tick down during the immunity period.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the charge.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of displacements for the cast time of the ability.
 * provides immunity to all forms of CC for the duration of the dash.
 * provides immunity to all forms of CC for the duration of the dash.

Removal
Most types of crowd control can be removed after it has been applied - with the exception of, the ability or item in question can still be activated while affected by the CC it removes, even when that CC normally precludes ability or item usage.

Stasis effects cannot be removed. Ground effect can be removed only by basic moving out from affected area. Nearsight effect can be removed only by active. Airborne effects are removable only by other move blocks (airborne effect, dash or blink); airborne effects will still apply for the rest of their duration if not removed by other airborne effect (although they can be prevented and removing their stun component allows to completely remove them by consecutively using own dash or blink). Stasis makes units untargetable and completely prevents ability usage even for abilities that can be activated under CC (thus making whether it can be removed or not a moot question).


 * removes all forms of CC.
 * removes all forms of CC.
 * (as )'s removes all slows.
 * removes all forms of CC.
 * removes all forms of CC.
 * removes all slows.
 * removes all slows.
 * removes all forms of CC aside from airborne and suppression.
 * The item active removes all forms of CC, including airborne effects if a blink or dash ability is used after activation.
 * active effect removes all forms of CC aside from airborne and suppression.

Reduction
Crowd control reduction reduces the duration of crowd control effects by a percentage equal to its value. Sources of CC duration reduction will stack multiplicatively with each other, not additively - successive buys can only approach, not reach, 100% reduction. Crowd control reduction can sometimes be referred to as Tenacity.

Ground, nearsight, stasis, suppression and move block part of airborne are not affected by crowd control reduction and will always apply for their full duration. Stun part of airborne effect is affected by crowd control reduction.

Potency Reduction
This effect is unique to the slow crowd control; potency reduction reduces the effectiveness, or percentage, of movement slows by a percentage equal to its value. Sources of slow potency reduction stack multiplicatively with each other, but do not interact with normal crowd control reduction.

Only slows are affected by potency reduction.

Self-CC
The following effects are comparable to crowd control, except that the effect is caused voluntarily and affects the user rather than a target. These effects cannot be removed by cleansing mechanisms and will ignore all crowd control immunity and reduction except in the case of self-slows, which will be affected by slow potency reduction (such as from ).


 * Self-Disarm: A champion that disarms itself is unable to attack for a duration. The target may still move and cast spells.
 * (on reload)
 * (on reload)


 * Self-Knockback: A champion that knockbacks itself is temporarily unable to attack and issue movement commands. The target may still cast spells.


 * Self-Nearsight: A champion that that is self-nearsighted has their own sight radius reduced by 900, while still benefitting from allied vision.


 * Self-Silence: A champion that silences itself is unable to cast abilities. They may still attack and use summoner spells.


 * Self-Slow: A champion that slows itself has reduced movement speed.
 * (with an enemy champion)
 * (when attacking a target)
 * (with an enemy champion)
 * (when attacking a target)


 * Self-Stasis:  A champion that puts itself into stasis cannot perform any action while also being untargetable and invulnerable.
 * (after death)
 * (cast over himself)
 * (self cast)
 * (self cast, after death)


 * Self-Stun:  A champion that stuns itself is unable to control its movement, attack, or use abilities.
 * (when colliding with terrain)

Cast Times and Channels
The casting (sometimes "charging") of an ability cannot be cancelled by the player or an enemy except by death. Forced actions (such as taunt) will have no effect for the duration of the cast, and using airborne effects to move the player will not affect the trajectory of the skill - which will start from the point of cast, not from the player's current location. Summoner spells and most items can still be activated while casting.

The channelling of an ability, by contrast, can be cancelled by hard CC, and will also automatically cancel should the champion attempt to perform another action (such as movement, casting another ability or attacking) - there do exist exceptions to this rule, such as cast while channelling, but these are usually specific coding allowances and not standard behaviour. Summoner spells and most items can typically be activated mid-channel without disrupting it.

Channelling and casting animations are generally not considered forms of crowd control, however disruptive they may be. There do exist several notable exceptions, however:


 * Channelled Self-Pacify: These abilities will make champion unable to issue attack commands, other abilities, or . The champion may still freely move and use other summoner spells while channelling. The only example also slows the champion for the duration.


 * Channelled Self-Slow: These abilities will slow the caster for the duration of the channel. In all cases the champion may freely move while channelling but may not issue attack commands.


 * Channelled Self-Root: These abilities will remove the caster's ability to control their movement and issue movement commands (included forced actions, such as fear).
 * (for the first 1 second of the duration)
 * (for the first 1 second of the duration)
 * (for the first 1 second of the duration)


 * Channelled Self-Stun: The following abilities have channels that the user cannot voluntarily interrupt (contrary to most channels which will be interrupted if any attempt is made to move, attack, or use another ability). This is effectively comparable to a stun.
 * (for the first seconds of the duration)
 * (for the first seconds of the duration)
 * (for the first seconds of the duration)
 * (for the first seconds of the duration)

Trivia

 * causes the target to dance.
 * If abilities that share cooldowns or are unique to different forms are counted separately, then possesses the highest number of crowd control abilities in the game, at six, with  and  tying for second place, at four. Otherwise, if they are counted as shared,  and  possess the most, at four.
 * , and  possess the highest number of unique crowd control types, at five.
 * , ,, and possess the second-highest, at four.  If  is counted as a form of, she also has four.
 * ,, , , , , , , , , , , , , (otherwise), , , , , , , , , , ,  and  each have three.
 * ,, , , , , , , , and  are the only champions in the game that can activate an ability while disabled. Of these, ,  and ,  can also remove the disabling effects.
 * ,, , , , , and are the only champions in game without any sort of crowd control inherent to their kit.