Accessory Refinements Guide

Where Refinement materials come from

Refinements use three new materials: Tetsu is Grade 2, Hagane is Grade 1, and Tamahagane is Special Grade. All three currently come only from the Curse Calamity Raid.

Curse Calamity has three difficulties:

The exact drop chances for all three materials are currently unknown. Do not treat any unofficial percentage as confirmed. A practical farming choice is the highest difficulty you can clear quickly and consistently, because faster reliable clears give you more completed reward rolls over time.

• Easy: level 1,000 required.
• Normal: level 2,500 required.
• Hard: level 5,000 required.

How to complete Curse Calamity efficiently

Curse Calamity is a staged raid rather than a single Overworld boss. You first defeat a group of enemies, then fight the first boss. After that boss falls, teleport to the next location and defeat the final boss to complete the raid and receive rewards.

Bring a Cursed Technique that combines good area damage with strong single-target attacks. Area damage speeds up the opening enemies, while boss damage shortens both boss fights. Compare real clear times instead of choosing difficulty only by level: a fast, consistent run is more useful for farming than a higher difficulty that regularly fails or takes much longer.

How Refinement levels affect stats

Every accessory starts at Refinement level 1 and can currently reach level 6. Each successful upgrade adds 10% to every stat on the accessory.

This is especially valuable on a strong endgame accessory with high Attack, Critical Damage, Cursed Energy, or technique-specific bonuses. The system improves the stats the accessory already has; it does not turn the wrong accessory into the best choice for your build.

• Level 1: base stats.
• Level 2: 10% more stats.
• Level 3: 20% more stats.
• Level 4: 30% more stats.
• Level 5: 40% more stats.
• Level 6: 50% more stats.

Every Refinement cost and success chance

If every attempt succeeds immediately, the minimum total cost from level 1 to level 6 is 5 Tetsu, 3 Hagane, 1 Tamahagane, 75 Cursed Crystals, 11,500 Lumens, and 1,250,000 Yen. This is the best-case cost, not the amount most players should expect to spend.

• Level 1 → 2 — 1 Tetsu — 5 — 1,000 — 50,000 — 90% — 10%
• Level 2 → 3 — 2 Tetsu — 10 — 1,500 — 100,000 — 70% — 30%
• Level 3 → 4 — 2 Tetsu + 1 Hagane — 15 — 2,000 — 250,000 — 35% — 65%
• Level 4 → 5 — 2 Hagane — 20 — 3,000 — 350,000 — 15% — 85%
• Level 5 → 6 — 1 Tamahagane — 25 — 4,000 — 500,000 — 5% — 95%

What happens when a Refinement fails

A failed Refinement does not destroy the accessory and does not move it back to a lower level. The accessory remains at its current Refinement level. However, every material and currency used for that attempt is consumed, so you must pay the full cost again.

The final upgrade has only a 5% success chance. Statistically, that is one success per 20 attempts on average, but it is not a guarantee or a pity system. You could succeed immediately or need more than 20 attempts.

At 20 attempts, the level 5-to-6 step alone would consume 20 Tamahagane, 500 Cursed Crystals, 80,000 Lumens, and 10,000,000 Yen. Treat those numbers as an average-cost illustration, not a guaranteed requirement.

Which accessory should you refine first?

Start with the accessory used by your main build and one you expect to keep for a long time. Do not spend scarce Hagane or Tamahagane on a temporary accessory that you plan to replace soon.

If you cannot afford the full route to level 6, level 2 or 3 is still a useful stopping point. Those first two upgrades offer up to 20% more stats with much better 90% and 70% success chances. Continue farming before committing to the 35%, 15%, and 5% stages.

Prioritize the accessory whose effect and base stats already support your build. For help comparing current options, use the Jujutsu Zero Accessories Guide before spending rare Refinement materials.

Common mistakes

• Do not assume unconfirmed material drop percentages are official.
• Do not choose Hard if slower or failed runs reduce your completed rewards per hour.
• Do not refine a temporary accessory just because you have Tetsu available.
• Do not split rare materials across several accessories before finishing your main one.
• Do not expect the 5% final upgrade to succeed within exactly 20 attempts.
• Do not confuse the best-case first-attempt total with a realistic guaranteed budget.
• Do not expect failure to downgrade the item, but remember that the complete attempt cost is lost.