No, its doesnt stack, Elemental Damage is counted separately. All of the Aminal Companion Skills are Magic Damage only and the Frost skills are Frost Damage.

Also, it will be 10% at Lv2. Pretty juicy passive.

Still hoping they provide the same buffs for Sorc's lightning/physical damage and DK's fire/poison damage. We need more unique synergies if we're going to get more skills in the game as things progress.

validifyedneb18_ESO wrote: »

Realised today how strange the wording on this tooltip is given that all elemental damage counts - to the best of my memory anyway- as magic damage.
Is elemental damage counted seperately, or is this tooltip strangely worded or does the 5% stack twice for frost?

The type of damage done (magic, poison, fire, physical, etc.) is a separate thing from the resource used by the ability. Just because something is a magicka skill does not mean it does magic type damage. So, Screaming Cliff Racer uses magicka as it's resource and does magic damage. It will gain 5% damage. Winter's revenge uses magicka as it's resource and does frost damage. It will gain 5% damage. Force Pulse uses magicka as it's resource and does fire, frost, and shock damage. The frost component will gain 5% damage, the fire and shock components will gain no extra damage.

Basically, this passive cannot stack because a damage tick can never be both magic damage and frost damage. They are mutually exclusive.