Diablo IV: How to Plan Your Mythic Upgrades Before Season 15

First, a correction worth making

If you arrived expecting Mythic advice for Season of Infernal Chaos, that season is long finished — Infernal Chaos was Season 10, and it started on 23 September 2025. The live season as of late July 2026 is Season 14, which began on 30 June 2026, running on build 3.1.1a after the 17 July patch.

That matters because the big Mythic change everyone is talking about is not live yet either. Blizzard confirmed it in the 3.1.1a patch notes as a Season 15 change, and Season 15 starts on 15 September 2026. So right now you are in a planning window: the rules you craft under today are not the rules you will craft under in September. This guide covers both, clearly separated, so you stop burning resources on a system that is about to change.

What Blizzard actually confirmed for Season 15

Straight from the 3.1.1a developer note (17 July 2026):

“In S15’s Horadric Cube, we’re removing Mythic reroll crafting and adding a direct upgrade to Mythic that preserves the original Unique Item. We’ll evaluate bringing back this rule for that specific crafting path only.”

The same patch also removed the “one crafted Mythic” equipment restriction, which previously capped you at a single Cube-crafted Mythic equipped at a time while drop-found Mythics were exempt. That cap is gone as of 3.1.1a — though the dev note explicitly warns they may reintroduce it for the new direct-upgrade path specifically.

Two things follow, and only two. Do not let anyone sell you more certainty than this:

• Confirmed: Mythic reroll crafting at the Horadric Cube is being removed in Season 15, replaced by a direct upgrade that preserves the original Unique item rather than rolling a random Mythic in its category.
• Not published: the material cost of that direct upgrade. Blizzard described the mechanic without listing numbers. Any guide quoting you an exact Resplendent Spark, Living Steel or Abstruse Sigil cost for the Season 15 direct upgrade is guessing. Check the Cube UI yourself when the season goes live.

How Mythic acquisition works right now (Season 14)

Before you plan for September, know what is actually live today. The short version: you cannot fully target a specific Mythic on the current build. You can narrow the pool, and that is it.

Route	Station	Cost	What you get
Random Mythic craft	Blacksmith	2 Resplendent Sparks + 50,000,000 gold	A random Mythic Unique
Narrowed Mythic craft	Jeweler (rune crafting)	2 Resplendent Sparks + named Legendary rune sets	A Mythic from a chosen item-type pool
Boss drops	Torment I+ Uber and Tormented bosses	Summoning materials	RNG within that boss’s table
Salvage	Blacksmith	1 unwanted Mythic	1 Resplendent Spark back

The critical detail people get wrong: picking the exact named Mythic at the Jeweler is no longer possible. Earlier seasons let you rune-craft a specific item. On the current build you choose an item-type pool that is guaranteed to produce a Mythic, not the one you named. Older guides describing exact-item targeting are describing a dead system.

Sparks come from salvaging Mythics you do not want (1 each) and from Season Journey and seasonal rank rewards. The loop is self-feeding: roll a Mythic, salvage it if it is wrong, get a Spark back, roll again at a net cost of one Spark per attempt.

The mindset shift, and why it matters now

The old habit was treating Mythic crafting as a lottery — accumulate attempts, spend them, absorb the bad outcomes. Under Season 15’s direct upgrade, that logic inverts. When you can convert a specific Unique you already own into its Mythic version, the question stops being “how many attempts can I afford” and becomes “is this particular Unique good enough to spend on.”

Which creates a very concrete trap between now and 15 September: salvaging duplicate Uniques. Right now a second copy of a build-defining Unique feels like clutter once you have one equipped. Under a system that upgrades your specific item and preserves it, a duplicate with strong Greater Affixes or a near-perfect roll is a future upgrade seed. Salvage it today and you pay for it with another farming cycle in September.

What to keep in your stash

• Keep the best copy of any Unique central to a build you might realistically run — including alternate classes and builds you have not committed to yet.
• Keep strong duplicates carrying useful Greater Affixes, especially ones that are painful to replace at equivalent quality.
• Keep near-perfect rolls. These are the ones worth a serious Mythic investment.
• Salvage clearly inferior copies, but only after you have protected a better version of the same item.
• Defer on anything you cannot judge yet because your endgame build is not settled.

A workable stash rule: designate one copy of each relevant Unique as protected, then measure every new drop against it. If a drop beats the saved copy, promote it and free the old one. That gives you the upgrade seeds without hoarding every duplicate you have ever seen.

Which Mythics are worth targeting

Pick your target before you spend anything. The current consensus priority list for endgame builds:

• Harlequin Crest (helm) — heavy damage reduction plus +4 ranks to all skills. Rated effectively mandatory across every class, because skill ranks and DR scale offence and survivability simultaneously. The safest first target for almost anyone.
• The Grandfather (two-hand sword) — very high weapon damage with major critical strike scaling. Current coverage calls it the strongest Iconic Mythic outright. The ceiling upgrade for Barbarian (Whirlwind, Bleed, HOTA) and 2H-scaling Druid builds.
• Tyrael’s Might (chest) — an offensive proc while at full Life on top of strong defensive stats. Best on casters that reliably stay topped up through barriers and DR.
• Andariel’s Visage (helm) — Lucky Hit poison nova with damage-over-time and attack speed bonuses. The pick for DoT builds: poison Rogues, shadow and poison Necromancers.
• Ring of Starless Skies — resource cost reduction stacking into a damage buff as you spend. Universally usable, strongest on high-APM resource-spender builds.

Below that tier, Heir of Perdition and Ahavarion, Spear of Lycander are strong when they match your archetype but are not the near-universal picks the five above are. If Heir of Perdition is your target, we have a dedicated craft route for it.

Your checklist between now and 15 September

1. Stop salvaging good duplicate Uniques. This is the single highest-value habit change. Protect quality copies of build-defining items.
2. Pick your Season 15 Mythic target now. Start from the slot solving your biggest problem — damage ceiling, survivability, resource sustain — not from whatever is rated highest in the abstract.
3. Farm the input, not just the materials. These are separate grinds. Holding enough resources does not make a weak base worth converting, and owning a great base does not mean you should spend it on a Mythic that no longer fits your plan.
4. Bank Resplendent Sparks rather than spending them on random rolls. With reroll crafting being removed and the direct-upgrade cost unpublished, dumping Sparks into 2-Spark random Blacksmith rolls right now is the least informed use of them.
5. Verify the Cube UI on day one of Season 15. The costs are not published. Read them in-game before committing your protected copies.

One caveat on the season itself: community reception to Season 14 has been mixed, with a widely-upvoted r/Diablo thread in early July arguing that Lord of Hatred lifted the game substantially while the new season ignored what made it work. If you are deciding how hard to push now versus saving effort for September, that sentiment is worth weighing.

While you are here, patch 3.1.1 also introduced a crafted-Mythic bug worth understanding before you spend anything — see how to mitigate the Season 14 crafted Mythic bug and our 3.1.1 Mythic drop rate test. Everything else lives on the Diablo IV hub.

FAQ

Is Season of Infernal Chaos still live?

No. Infernal Chaos was Season 10 and ran from 23 September 2025. The current season is Season 14, which started 30 June 2026.

When does the direct Mythic upgrade arrive?

With Season 15, starting 15 September 2026. It is confirmed in Blizzard’s 3.1.1a patch notes but is not on the live build today.

What does the direct upgrade cost?

Blizzard has not published the material cost. The patch note describes the mechanic only. Treat any specific figure you see before launch as unverified.

Can I still target a specific Mythic right now?

Not exactly. On the current build the Jeweler lets you choose an item-type pool guaranteed to yield a Mythic, but not the specific named item. Exact-item rune targeting was removed.

Should I spend my Resplendent Sparks now or hold them?

Holding is the more defensible call. Reroll crafting is being removed, the replacement’s cost is unknown, and a 2-Spark random Blacksmith roll is the least targeted option available. Unless you need an immediate power spike to clear content, wait.