I predict it's gonna be Ysayle's outfit
We haven't had an NPC outfit for a while

And this case it's gonna be a split set:
Iceheart Robe
Iceheart Armlets
Iceheart Bottoms
Iceheart Thighboots

They will share the model with the acolyte set you get from Sastasha/Copperbell
it will be undyable, of course.

It will costs 12.00USD and will not include anything else.