Which enemy abilities are affected by silence?

Torchlight 2 has many status effects that can be applied to monsters. However, they seem to be poorly documented (if at all.) One of these is silence, which has a spell dedicated to it, is a byproduct of the nether imp's attack, and is an effect produced by many magical weapons.

Its official spell description is this:

Silences enemies within 8 meters, preventing them from using most skills.

Which abilities/monsters are affected? (The only one that I think I've noticed is the basilisk's immobilizing gaze.)

Silence is not dependent on enemies, instead it is dependent on the Skills. Some skills can be silenced and some can't be silenced. There is a flag in the game files for the abilities which can be silenced.

By looking at some .dat files you can see which abilities can be silenced.

Example: The Basalisks in Act II. They have two skills. Basalisk Gaze and Firebreath. Firebreath has "CAN_BE_SILENCED:false" in the .dat, so this skill can't be silenced and they are going to use it against you even if you cast silence.

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