Diablo 4 Season 15 Horadric Cube: 4 Official Recipes

The Horadric Cube in Diablo 4‘s Season 15 has four crafting recipes that matter for gearing: Affix Value Reroll, Horadric Reroll, Upgrade Direct Item to Mythic, and Amalgamation. Season of Hell’s Legacy went live on September 15, 2026 on patch 3.2.1, and two of these recipes — the reroll pair — are brand new to this season, while the Mythic crafting update reworks a system that already existed. This guide covers what each recipe actually does, what it protects versus what it wipes, and which one to reach for depending on the item sitting in your inventory.

Each of these four recipes solves a different gearing problem, and mixing them up wastes materials and time on the wrong item.

Material quantities for all four recipes are not stated in the official Season 15 overview. A BlizzCon 2026 panel demo, reported by Output Lag, showed on-screen text for Affix Value Reroll listing a cost of one Attuned Primordial Dust and 100 Raw Primordial Dust on a Rare-or-better item, with Horadric Resin optional — but that was a pre-launch BlizzCon demo, not the live 3.2.1 patch notes, so treat those figures as unconfirmed for the current build. The same report noted the materials for Horadric Reroll were never shown on screen, and neither recipe carried a stated usage limit during that demo.

You like the item’s protected traits but want its base affixes rolled again

Use Affix Value Reroll. It rerolls all base affixes on equipment or a Talisman item at once, leaving Greater Affixes, Enchanted affixes, Tempers and valid Transfigurations alone — the current base rolls are gone, the protected ones stay.

You have a Legendary+ Charm or Seal and want a fresh base

Use Horadric Reroll instead. It fully randomizes the Charm or Seal’s base affixes without disturbing Set Bonuses or Unique/Mythic charm powers, which is the move for a clean slate on a Charm or Seal.

You have a perfected Unique and want it Mythic

Use Upgrade Direct Item to Mythic (Unique in, Mythic out, 1:1). Confirm the item isn’t Unmodifiable first, and remember only one Crafted-tag item can be worn at a time — you can still craft another later.

You have duplicate Soul Splinters

Use Amalgamation to combine matching type-and-rarity Splinters into the next tier rather than letting duplicates sit unused.

Affix Value Reroll is the recipe for an item whose protected traits you want to keep while every base affix gets rolled again — it is not a single-line fix. It works on both equipment and Talisman items — Charms and Seals — and rerolls all base affixes on the item while protecting the traits worth keeping: Greater Affixes, any Enchanted affixes, Tempers, and Transfigurations, as long as the Transfigured item isn’t Unmodifiable. That’s the mechanism the overview describes: you keep the parts of the item that took real luck or investment to get, and all of the ordinary base affixes are rerolled together — so use it when you are happy to lose the current base rolls, not when one line is wrong and the rest are perfect.

What the overview does not say matters here too. Greater Affixes are on the protected list, so the ones already on the item stay; what the overview does not say is whether a rerolled base affix can come back as a new Greater Affix, and it lists no material costs or repeat/usage limits for this recipe. That absence is specific to the official Season 15 overview text checked in full — it isn’t a statement that the recipe has no cost, just that the published document doesn’t say what it is.

Horadric Reroll sits next to Affix Value Reroll for a narrower job. It’s available only for Legendary and better Charms and Seals, and it fully randomizes all base Affixes on those items without touching Set Bonuses or Unique/Mythic charm powers. The distinction from Affix Value Reroll is specific: unlike Affix Value Reroll, Horadric Reroll will not change the Charm Set Bonus Affixes on Seals — just the base Affix. In practice, that means Horadric Reroll is a full reset button for a Charm or Seal’s ordinary lines when you want to start over rather than nudge one line, while Affix Value Reroll is the tool when you want to keep specific protected traits and only fix the rest.

The BlizzCon demo covering both recipes didn’t display materials for Horadric Reroll at all, and confirmed neither reroll recipe had a stated usage cap during that showing. Whether either recipe has a per-use gold or Primordial Dust cost in the live 3.2.1 build isn’t published in the overview.

Mythic Uniques can be created three ways in Season 15: Horadric Cube’s Upgrade Direct Item to Mythic, the Jeweler’s Rune Crafting into Mythic Uniques, and the Blacksmith’s Forge into a Mythic Cache. The Cube route is the one for a specific, perfected item. Upgrade Direct Item to Mythic in the Horadric Cube is more expensive than the Blacksmith or Jeweler recipes, but it performs a total 1:1 transfer — put in a Unique with ideal affixes and dialed-in Tempering and Masterworking, and it comes out as the Mythic version of that exact item, retaining all affixes and modifications. The one restriction is that it can’t be used on an Unmodifiable item.

Mythic Uniques made through the Cube’s Upgrade Direct recipe carry a Crafted tag, and only one Crafted-tag item can be equipped at a time — but Mythics made through the Jeweler’s Rune Crafting or the Blacksmith’s Mythic Unique cache carry no Crafted tag. That means you can equip several Mythics from Jeweler, Blacksmith or drop sources alongside a single Cube-crafted one. The limit is on equipping, not on crafting: the overview says nothing about how many Crafted-tag Mythics you can make or keep, only that one can be worn at a time. The input is a Unique — the BlizzCon panel recap puts it as “upgrade an item directly from Unique to Mythic with all affixes intact” (Blizzard, What’s Next panel recap). A developer’s note on the same page adds context: Iconic Mythics remain Mythic-quality only after PTR feedback against giving them Unique versions, and the Blacksmith gained a second cache option that rolls only for Iconic Mythics at the same cost as the regular Mythic Uniques cache. This is a real overhaul from Season 14, where the Cube’s old Mythic recipe was a random draw for the chosen gear slot rather than a targeted upgrade, and its cost was trimmed from 5 to 4 Pandemonium Fragments in patch 3.1.1 — a system Season 15 replaces outright. For the farming side of getting a base item worth feeding into this recipe, the Mythic Unique farming guide covers the broader gearing loop this recipe plugs into.

Soul Splinters are special gems for the Season of Hell’s Legacy, each tied to a Prime Evil, minor demon or artifact. They drop as Magic, Rare, Legendary, or Unique rarity, and Amalgamation in the Horadric Cube upgrades Soul Splinters of the same type and rarity to the next highest rarity. You can equip up to three Soul Splinters among your available jewelry slots. The eight named Soul Splinters are Splinter of Anguish (Andariel), Splinter of Sin (Azmodan), Splinter of Lies (Belial), Splinter of the Black Soulstone, Splinter of Pain (Duriel), Splinter of the Mother (Lilith), Splinter of Hellfire (Na-Krul), and Splinter of Damnation (Skarn).

Third-party coverage doesn’t agree on how to describe the rarity tiers here. One community wiki labels the tiers Lesser, normal, Greater, and Abyssal, while a different outlet lists five tiers including a Common rung — both differ from the official overview’s own four-tier Magic/Rare/Legendary/Unique language, so this article follows Blizzard’s own terms rather than either third-party naming scheme.

For the full effect list and how Soul Splinters differ from the separate Splinters of Evil reputation system from the seasonal questline, see the guide comparing Splinters of Evil to Soul Splinters.

The overview doesn’t state whether the two new reroll recipes or the Mythic crafting update persist for Eternal (non-seasonal) characters once Season 15 ends. That’s a real gap worth flagging because the same document is explicit elsewhere: the nine Legacy Uniques introduced this season are described as permanent additions available on both Seasonal and Eternal realms. Soul Splinters get the opposite framing — they’re explicitly called special gems for the Season of Hell’s Legacy, tying them to the season by name rather than stating they carry forward. Some of this crafting groundwork was visible earlier too; the Mythic crafting changes and Soul Splinters both appeared during the PTR 3.2.0 test window in early August 2026, ahead of the September 15 launch. For how the PTR version compared to what actually shipped, see the breakdown of what the PTR showed versus what shipped on September 15.

Sources and Confidence

This table separates what the studio has confirmed from what comes out of press previews, and what is still just circulating. Each claim below is tied to the post and the game version it describes.