Codex of Power in Diablo 4

What does the Codex of Power do?

The Codex of Power is a new system that rewards players with a Legendary Aspect after completing one of the game's over 120 Dungeons. A Legendary Aspect allows a player to upgrade a Rare or Legendary item with a specific Legendary affix. The system affects all of a player's characters.

Completing Dungeons

Each Dungeon is associated with a Legendary Aspect reward that the player is shown beforehand in the Dungeon's description. Most of the Aspects are Class-based, meaning that players can strategically choose Dungeons with rewards that are relevant to their builds.

D4 Maulwood Dungeon with Slaking Legendary Aspect reward
Dungeon with a Barbarian Legendary Aspect reward

List of Legendary Aspects

As of Open Beta, there's 114 Legendary Aspects to unlock in the Codex of Power; however, come launch, there will probably be more. They're separated into 5 types:

Diablo 4 Codex of Power interface
Codex of Power UI to view unlocked Legendary Aspects
Diablo 4 SteelSeries hardware
D4 Aerox 5 Mouse SteelSeries Aerox 5 Wireless Diablo 4 mouse
D4 Arctis Nova 7 SteelSeries Arctis Nova 7 Diablo 4 headset
D4 QcK Mousepad SteelSeries QcK Diablo 4 gaming surface

Imprinting an item with the Codex of Power

Players can take their Rare or Legendary item they wish to upgrade with a Codex of Power Aspect to the Occultist, who will "imprint" the Aspect onto the item.

Occultist interface for imprinting a Codex of Power Aspect
Codex of Power Legendary Aspects can be utilized at the Occultist NPC

Infinite-use Aspects

Unlike Aspects acquired and extracted from monster drops, which are one-time-use only, Codex of Power Aspects can be applied infinite times to Rares and Legendaries (assuming the player can afford the Occultist's Gold and Veiled Crystal fee).

Ensures weakest Legendary affix roll

While the Codex of Power system is convenient, there's a catch: the range of the Aspect's Legendary affix imprinted on an item will always be the lowest possible value [1] (e.g., for an affix range of 10-20%, 10% would always roll). This makes the Codex of Power Aspects weaker than those extracted from monster-dropped Aspects.

"Codex powers are always weaker versions of what can roll on an item. Basically, Legendary powers can roll on a range, and the Codex version will always roll the minimum value. The Codex is a deterministic way to hunt for a specific power you want, but you'll eventually want to farm for the random Legendary drop in order to get an improved version."
Diablo IV guide author Rhykker · Diablo YouTuber · YouTube svg icon

Only provides half of possible Legendary Aspects

Another drawback of the Codex of Power is that it only offers players access to half of the Legendary Aspects in the game. For the rest, players will have to acquire Legendary items from monster drops and take them to the Occultist to extract the Legendary affixes.

"The devs estimate that half of the Legendary powers in the game can be acquired by the Codex"
Diablo IV guide author Rhykker · Diablo YouTuber · YouTube svg icon
Trending hardware for Diablo 4
Alienware AW3423DW Dell Alienware AW3423DW ultrawide monitor
Asus ROG Ally ASUS ROG Ally handheld gaming system
Secretlab Titan Evo Secretlab Titan Evo Gaming Chair
Xiphoid Barbarian avatar

Xiphoid has been playing Diablo since the original's release in 1997. He made one of the largest Age of Empires sites in the late-'90s and early-'00s. Now, he runs, a premier Diablo 4 fansite.


Article Source Date
1. Rhykker summarizes a preview build of Diablo 4 Rhykker


Ver Change Date
Update icon svg Beta Refreshed guide with Open Beta Codex of Power information
Upload icon svg Beta Published original