The Patch 10.2 PTR is now available for testing, and while the encounter journal is not fully complete, it includes a full raid boss list for Amirdrassil: The Dream's Hope!
The new raid features nine bosses composed of corrupt defenders of the Emerald Dream to smoldering servants of the Elemental Plane of Fire, culminating in a showdown with the Primal Incarnate of Fire: Fyrakk the Blazing!