PoE Eldritch Evocation: Defeat Witnessed Bosses or Activate Eldritch Altars

Eldritch Evocation

Defeat Witnessed Bosses or Activate Eldritch Altars while in Maps that are affected by an Atlas Astrolabe the specified number of times.

• Defeat Witnessed Map Bosses (0/100): Defeat bosses that are being witnessed by The Maven.
• Activate Eldritch Altars (0/200): Click on altars spawned by the Searing Exarch or Eater of Worlds.

To complete the Eldritch Evocation challenge in Path of Exile 3.28 (Mirage League), you must interact with Atlas Astrolabes to create "Shaped Regions" and then either defeat Maven-witnessed bosses or activate Eldritch Altars within those specific maps.

How to Use Atlas Astrolabes

Astrolabes are a new currency in 3.28 that apply a "Shaped Region" (a "blob" of influence) to a cluster of maps on your Atlas.

• Obtain Astrolabes: Astrolabes are a guaranteed drop from memory bosses, and have a chance to drop from final map bosses after completing the quest Threads of the Originator and socketing the Originator Voidstone into the Atlas.
• Apply them: Speak to Eagon Caesarius, select "Apply Astrolabe," right-click the Astrolabe in your inventory, and click a map on the Atlas to influence it and its surrounding maps.
• Run the Maps: Enter any map that is visually encased in the Astrolabe's "blob" on your Atlas.

Strategy Tips

• Stacking Progress: Each time you complete a map in a Shaped Region, the region shrinks and the remaining maps gain more difficulty and better rewards.
• Maven vs. Eldritch: Since you cannot have both Maven and Eldritch (Exarch/Eater) influence active simultaneously on a single map, you must choose one path per map. For Eldritch Altars, run Searing Exarch or Eater of Worlds influence in T14+ maps to spawn altars. For Witnessed Bosses, activate the Maven's Beacon and run maps she hasn't witnessed yet in that tier.
• Synthesised Stability Keystone: If you prefer running a single favorite map layout, allocate the Synthesised Stability Atlas Keystone. This allows you to run the same map repeatedly to clear the Shaped Region instead of it shrinking away from that specific layout.
• Memory Vaults: After fully clearing a Shaped Region, speak to Eagon to access a Memory Vault, which contains high-value rewards similar to Grand Heist Curios.