Arm's Length
Arm's Length
“Creates a barrier nullifying most knockback and draw-in effects.
Duration: 6s
Additional Effect: When you are struck by a physical attack, the striker will be afflicted with Slow +20%
Duration: 15s— In-game description
Arm's Length is an action unlocked at level 32. It is available for Melee DPS, Physical Ranged DPS and Tank.
Additional Information
The 
Slow is a reduction to enemies' auto-attack speed and global cooldown time. This makes Arm's Length in effect a defensive ability in addition to nullifying knockbacks. Therefore, it should be used as part of a tank's regular defensive cooldown rotation when pulling enemies in dungeons. Note that the Slow debuff should not be confused with 
Heavy, which is a reduction in movement speed.
Not all knockback and draw-in effects can be prevented. In some newer duties, these will be indicated with purple knockback telegraphs.
The analogous anti-knockback ability for 
Magical Ranged DPS and 
Healers is 
Surecast.
Interactions
This action prevents 
Rescue from dragging the player.
On a 
Warrior, if both Arm's Length and 
Vengeance are active at the same time, then enemy attacks cannot strike the barrier of Arm's Length, thus the Slow effect cannot activate. This is because Arm's Length's barrier and Vengeance are both considered "counter effects", only one counter effect can be considered active at a time, and Vengeance's effect has a higher priority than Arm's Length.
History
Patch 5.0 (2019-07-02):
- Now acquired at level 32 (previously level 12).
- Recast time has been increased from 60 to 120 seconds.
- Now available as both a tank role and ranged physical DPS role action.
- Effect duration has been increased from 5 to 6 seconds.
Patch 4.0 (2017-06-20): Added, replacing 
Haymaker.