Path of Exile 2 is full of unique items that can help strengthen builds, but the Prism of Belief is one of the most underrated. Endgame builds in PoE 2 can often feel like minor upgrades, but these minor upgrades add up to give incredible strength. To reach this point requires a lot of grinding with a fair bit of luck, but for a game as difficult as PoE 2, it can be the ultimate show of strength and reward.
Unique items can take builds to another level and shorten these grinds. A prime example of this is Path of Exile 2's Astramentis, an amulet that gives massive buffs to all three attributes. This not only gives it amazing flexibility, but massively boosts the key stats any class will need for the most success. Though not all Uniques can be as flexible as this, the large majority provide massive buffs to certain playstyles in some fashion.
How To Get Prism of Belief Diamond
The True Endgame
The Prism of Belief Diamond can only drop from defeating The Arbiter of Ash in POE 2 on Difficulty 4. Since this is the maximum difficulty, as of now, this will not be the easiest fight, but it is well worth the effort. Still, the diamond only has a 20% chance of dropping, so it is likely to take multiple attempts to get even one. The Arbiter has high resistance to Fire, Lightning, and Ice, meaning builds revolving around those will need debuff methods. He will mainly deal Physical and Fire damage, so those are the best defenses to have when facing off.

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To reach the Arbiter on Difficulty 4 means defeating him three previous times on lower difficulties. This means that players will be spending a lot of time on maps getting to this difficulty, and then defeating the Arbiter multiple times in hopes of the perfect jewel drop. Luckily, maps can also be filled with Ritual Altars that can drop highly coveted Omens used to trade for other items in Path of Exile 2's currency exchange.
How To Use The Prism of Belief Diamond & All Its Effects
As Simple As Any Other Jewel

Luckily, once acquired, the Prism of Belief is just as easy to use as any other jewel. Simply find an open jewel socket and slot the diamond into it to trigger all of its effects. The one tip to stand by in this regard is not to rush to any slot, or use an unnecessary one just to use this diamond. Most builds will naturally unlock a handful of jewel slots on their optimal path, so even if it means waiting a while, it will be worth it to have the best skill pathing.
The Prism of Belief diamond is one of the strongest jewels in the game due to its ability to raise the level of a random skill. At worst, this will be a plus one, all the way up to a plus three. The tricky thing about this is getting it to roll for the desired skills and then roll at the highest possible increase. This means a lot of grinding could be in the future for any player who wants to use even one of these powerful unique jewels for builds, such as the best endgame Sorceress in PoE 2.
This unique may be a long grind, but it is well worth the effort. Stacking multiple plus threes on one skill can lead to incredible damage numbers, whereas the alternative is to spread everything out across multiple abilities. Regardless of the method used, this diamond can take builds to a level where no threat is too big. However, to achieve this strength, players must learn how to get the Prism of Belief Diamond in Path of Exile 2.

Released December 1, 2024
ESRB M For Mature 17+ // Blood and Gore, Nudity, Violence
Developer(s) Grinding Gear Games
Publisher(s) Grinding Gear Games