Oh yes it is.
We already know one thing, that is 100% innovative and has never been done before (as far as i know).
The boss will have 30 different skills in total, but when you fight the boss he will use a randomly selected pool of thsoe 30 skills, which will make each fight unique.
Just in Case you missed those major announcements and teasers:
Here the initial announcement:
Something Lurks Within the Monolith - General - Last Epoch Forums
And here teasers of some of the skills
Lets Look At Some of the Shade of Orobyss’s Many Skills! - General - Last Epoch Forums