Seven new super versions of Pinnacle Boss fights were introduced through Atlas Keystone Passives. These battles are extremely challenging, so only approach them if your character is convincing.
[PoE 3.25] UBER BOSS TACTICS — Uber Guides: Sirus, Exarch, Maven, Uber Elder, Eater, Cortex, Shaper
The Uber Elder is one of Path of Exile's most challenging boss battles, as players must fight both The Shaper and The Elder at the same time.
Venarius, Sirus, The Maven, The Searing Exarch, The Eater of Worlds, The Shaper, and The Uber Elder are six new capstones that generate uber versions of Path of Exile's boss summits.
To face the Uber Elder, you must collect all four of his fragments from the Shaper and Elder battles and then place them in the map gadget. These are Knowledge Fragment (Shaper), Shape Fragmentation (Shaper), Terrorist Fragment (Elder) and Emptiness Fragment (Elder).
