Calamity Fragments (Uber Arbiter)

If you want to take on the Uber version of Path of Exile 2 Currency the fight, you'll need Calamity Fragments instead.

Unlike the Crisis Fragments, Calamity Fragments are earned through increased challenge. They replace the drops of Crisis Fragments when your Atlas has 10 points allocated on the Boss Tree. These fragments can only be obtained after defeating the Citadel bosses in their hardest versions.

Currently, as of patch 0.3.0c, no confirmed data proves that Calamity Fragments directly increase the Arbiter's loot drops. However, community testing suggests they may bias the loot table toward rarer unique items and valuable currency, reducing the chance of common drops.

There's also a unique mechanic to note:

If you die during the Uber Arbiter fight, your instance is downgraded to a regular Arbiter encounter. You can reattempt, but the Uber modifiers will be gone. This mechanic ensures that failure isn't a full loss, but also means you won't get the Uber-tier rewards unless you win in one go.

Unlocking the Ten Boss Tree Points

To unlock the Calamity Fragment drops, you need ten Boss Tree points. These points are earned by completing progressively harder boss challenges. You unlock them in sets of two, requiring increasingly powerful waystones and maps.

Here's the breakdown:

Points 1-2:

Slay a Map Boss in an Area Level 79+ zone with 6+ modifiers.
Any Tier 15 Waystone map will reach this level requirement.

Points 3-4:

Same as above, but in Area Level 80+ maps.
This requires a Tier 16 Waystone, or a Tier 15 boosted by Irradiation (via Precursor Tablets, Organised Forces, or certain Atlas Corruption effects).

Points 5-6:

Defeat an Anomaly Map Boss in Area Level 79+ with 6+ modifiers.
These maps are significantly harder but drop improved rewards and fragments.

Points 7-8:

Slay a Citadel Map Boss in Area Level 79+ with 6+ modifiers.
Completing this milestone also awards a Crisis Fragment, progressing you toward the Standard Arbiter fight.

Points 9-10:

Defeat the Arbiter of Ash in either the Standard or Uber version.
Once these are unlocked, all future Citadel boss kills will begin dropping Calamity Fragments instead of Crisis ones, provided your points remain allocated.

These points can be earned in any order, as long as the difficulty requirements are met. You don't need to cheap POE2 Currency follow a specific layout - any ten Boss Tree nodes will qualify for upgrading your fragment drops.