Kanai’s Cube (the KC or Cube) is a new item coming to Diablo 3 in Patch 2.3, set for release in August 2015. It harkens back to the Horadric Cube of Diablo 2, giving players the ability to convert or break down legendary items and gain bonuses from their special properties.
The biggest bonus from this item is the ability to grant a character 3 legendary properties from items, even when the items are not being worn. The initial iteration calls for 1 bonus from armor, 1 from jewelry, and 1 from weapons, which players would enable much like Passive skills.
The KC will be further evaluated once the Patch 2.3 PTR goes live, and all information on this page is tentative until Patch 2.3 goes final.
Kanai's Cube
The initial details came from Blizzard's Patch 2.3.0 preview on June 23, 2015:[1]
New Artifact: Kanai’s Cube
Those who played Diablo II might remember the Horadric Cube, a unique device which allowed you to combine items. Useful as it was, it was easily surpassed in power by the item from which it originated, Kanai’s Cube. In Patch 2.3.0, players will be able to discover this powerful ancient relic and utilize its incredible potential, including the ability to break down Legendary items and equip their special effects as passive skills (which are separate from your other passive skills), convert crafting materials from one type to another, and so much more.
Additional details were added in a reply by a community manager:[2]
How many passives can we use at same time? Does it take a passive skill slot to equip?
Tyvalir: There’s been some confusion about how these passives work, so let me clarify.
With the current plan, the passives you get by breaking down Legendary items with special effects in Kanai’s Cube do not replace passive skills on your character, but are instead part of a separate set of passives that are specifically stored within the cube. You can store as many special effects as possible in the cube, but only a limited number can be active at a given time (currently, this is three: one weapon effect, one armor effect, and one jewelry effect).Theorycrafting Kanai's Cube
The concept of adding three "free" legendary powers thrilled the community, and theorycrafting ideas flooded forth.[3] A few of the main ideas:
- Getting the RoRG property from the Cube grants much more item variety while still getting six-piece set bonuses. (Which is a big buff since the RoRG stats are generally much worse than other rings.
- This partially fixes the "Ancient weapon problem" since players can add the special legendary property from the ultra-rare weapon required for their build without having to find that item in Ancient form.
- Defensive buffs abound:
- Wearing an immunity Amulet + getting a second immunity from the Cube.
- Gaining CC immunity from Ice Climbers.
- Gaining full time double Unity buff without having to wear the ring.
More details on the Cube will be revealed once it goes testable on the PTR, including how it works for crafting materials.