Root

Root (formerly known as Ensnare and Entangle) is a status effect that prevents affected units from moving, and from casting some mobility spells.

Mechanics
Root does not prevent a unit from moving by setting its movement speed to 0. It instead impairs movement in the same way as stuns do. They also do not interrupt the move order, so that the unit resumes moving towards its destination as soon as the root expires.

Root also does not interrupt a unit's attack or spell cast orders. If a unit is attacking or midst a cast animation, getting rooted neither stops it from attacking, nor cancels the cast of the spell. The unit continues executing those orders normally. If the unit's attack target or spell target gets out of range while the unit is rooted, it starts moving towards the target to attack it or cast the spell on it as soon as the root expires, similar to how the unit resumes its move command.

There are a few sources of roots which fully stop any of the unit orders, so that it does not resume moving, and does initially get its attack or spell cast canceled. However, this is caused by the source ability, and not by the root mechanic. The source ability orders the target to stop any actions it is currently taking. After the initial stop order, the unit can again be ordered to move, attack or cast a spell, so that it executes them as soon as possible, either while still rooted if it is an attack or spell cast command, or once the root expires if it is a move command, or the target is out of range.

Similarly, some sources of root prevent a unit from attacking while rooted. This is again not a mechanic of root. In these cases, the source abilies also apply a disarm along with the root.

Roots may or may not interrupt the target's channeling spells. This trait varies from spell to spell and is not consistant throughout. The same applies to root's interaction with invisibility. Some sources of root apply true sight over the affected units, while others do not.

A consistant trait of roots is their ability to disable numerous mobility spells. Since a root is not a hard disable, several blink, pseudo-blink and teleport spells are disabled while rooted, to prevent an easy escape. However, although it prevents casting those spells, it does not cancel them when getting rooted while the spell is already cast. In such cases, the unit remains rooted at its new location. A list of disabled spells can be found below.

Rooting abilities
The following abilities root enemy units:

Self-rooting abilities
Some abilities root the caster to prevent them from performing certain orders like moving or attacking.

Disabled by roots
The following abilities are disabled by root: