Slow debuff

Is it only a movement speed debuff or total speed?

A MS debuff only. Reduced AS is a separate debuff, its visualized as a broken sword above the target’s head.

You sure about that Hellcat? Because there are three different types of ‘slow’ in skills:

Slower target movement (like on grasping vines base skill)
Slower target attack (like on grasping vines modifier entangling vines)
Slow target (like on Nidallia’s Hidden Hand)

I was under the impression that the “Slow target” one was basically the resistible form of -X% Total Speed

I completely forgot about the third type, being rare.
You are right, there’s also total speed debuff.

I was asking about the Slow because of http://www.grimtools.com/db/items/8017 specifically.