Channel

A channel is a trait of certain abilities which is interrupted by crowd control effects that inhibit casting. These effects are: airborne, forced action, silence, disrupt, sleep, stasis, stun, suspension, and suppression. When a caster activates a channeled ability, the caster stops performing any previous actions.

Channels cannot begin if the caster becomes unable to cast abilities.

While the effects of the ability are present the caster is channeling the ability. In most cases, the caster can interrupt the channel by performing an action, such as moving, attacking, or casting an ability. Some channels cannot be canceled at all, which prevent the caster from performing any act. Channels that require the caster to be out-of-combat means that entering combat interrupts their channel.

The channeling status disables other effects specified by the ability from being used. This includes attacking, moving, casting abilities, and using summoner spells or item actives.

List of Channeled Abilities

Classic Channels

The following channeled abilities are consistent with one another in terms of being interrupted by the forms of crowd control stated above.

Champion abilities

Item actives

Black Spear

Movement Channels

The following channeled abilities involve movement of the caster, which mostly includes by dashing or blinking, but is not limited to those two. This means that they are subject to being interrupted by crowd control effects that inhibit movement in some form, although not all of them are. These are: ground and root.

Champion abilities

Summoner spells

Objective Channels

The following channeled effects are also interrupted by entering combat or taking damage.

Champion abilities

Spells

Recall and Empowered Recall cannot be interrupted by damage in the last 0.1 seconds of their channels, aside from crowd control effects that naturally interrupt channels, such as silence and displacements. Note that root and grounding do not belong to that and thus do not interrupt the channel at any point by themselves.

Unstoppable Channels

Sion performing Unstoppable Onslaught and nullifying a crowd control effect that would otherwise *interrupt* his **channel**.

The following channeled abilities cannot be interrupted by crowd control and are only stopped by death. Note that all non-objective channels can be unstoppable as long as the user is crowd control immune in the process of doing so (e.g. Morgana could place her Black Shield on a channeling target and they would be considered unstoppable while the shield holds).

Champion abilities

Aurelion Sol's Voice of Light
Irelia's Defiant Dance
Pantheon's Aegis Assault, Empowered Aegis Assault, and Grand Starfall (second channel)
Sion's Unstoppable Onslaught
Urgot's Mercy

Item actives

Eye of the Herald

Uniquely, Unstoppable Onslaught is a channeled ability which additionally grants him crowd control immunity during the channel, therefore it cannot be interrupted as any attempt at cast-inhibiting crowd control will be negated.

There are a few exceptions, however:

The ability still be interrupted by death, as with all other channels. If so, the effect will end as if he collided with terrain or an enemy champion, dealing the damage and stunning and knocking up enemies around his current location immediately.
Due to a bug with Roar of the Slayer, he can occasionally cast his ultimate despite being rooted. In this case, he will stand in place until the root's debuff duration ends. During this time, the damage, stun duration and movement speed granted by the ability will still ramp up, and enemies that come into contact with him will be affected by the collision normally.
- The same bug allows him to cast his ultimate during crowd control that inhibits casting and movement abilities. If he starts charging the ability while stunned, airborne or silenced for example, the channel will be interrupted almost immediately, and he will perform the same leap as he does when the channel ends at maximum duration or is ended via its recast.
An allied trigger of the Blast Cone's airborne effect is not considered hostile crowd control and will thus disregard his crowd control immunity, interrupting his ultimate in the process. He will turn to face the direction in which he would be knocked into, then initiate the leap as if he collided with an enemy champion or recasted the ability the ultimate or was affected by an enemy's hard crowd control, overriding the initial airborne effect of the plant.
If he is put into stasis by an allied Bard's Tempered Fate (does not count as hostile crowd control in this case), he will attempt to leap forward (he can't while in stasis however) then initiate the area of effect as if he engaged in a collision. The ability does not appear to go on cooldown for a few seconds according to the HUD but trying to cast it does not bring any result. The steer and channel indicators do not disappear however and he is still able to perform actions as if he were not channeling.

Since Unstoppable Onslaught is a channeled spell, Kalista's Fate's Call will wait with its effect until the channel has ended, dragging him back to her across a potentially massive distance. The pull transpires immediately after the channel ends, but he will still leap forward despite not colliding with anything. The area of effect still occurs in the landing spot he would've stopped at.

Charged Abilities

Varus **charging** up Piercing Arrow to increase its range. The lesser circle defines the **current** range output, while the greater circle signifies the **maximum** range output. Most charged abilities have a default spell indicator to display the respective range.

A charged ability has two activations - the first begins the charging and the second will fire the ability. While using quick cast, the player must keep the hotkey held down to charge the ability and it will fire upon releasing the key. For most charged abilities, the caster is still able to move freely including the use of Flash and Dark Passage.

Charged abilities will cancel if their channel duration permits. If stated otherwise, the recast will be automatically initiated.

Charging is a sub-classification. The forms of crowd control that will interrupt a charged ability depends on the ability's super-type.

Champion abilities

Summoner Spells

Hexflash

Casting Times

Most abilities have a very brief casting time that will interrupt other actions, such as movement or attacking (most will automatically have the champion continue in their previous actions, although some will interrupt previous actions indefinitely). These casting times cannot be interrupted by any other effect than the caster's death, unless it was protected by resurrection. Casting times will display like the channeling bar above the HUD.

Notable examples are Ezreal's Arcane Shift and Tristana's Rocket Jump, who will still respectively blink or dash if they were crowd controlled during the cast time, which is their intentional behaviour but often misunderstood as a bug. These can even overwrite displacements, such as Blitzcrank's Rocket Grab, completely nullifying the displacement but not the applied stun, which will still be in effect after the cast time if duration permits.