Precious Fossilized Core

Max-level stats (Lv60)

ATK (Lv.60)

594

Impact (Lv.60)

15%

Rank

A

W-Engine effect

Rank AStun

Behemoth Hunter

When the target's HP is no lower than 50%, the equipper inflicts 10% more Daze to the target. When the target's HP is no lower than 75%, this bonus is further increased by 10%. *Stats are shown at base level

Overclock Table (★1 → ★5)

Official values straight from the publisher — every duplicate copy Overclocks the passive by one star, capped at ★5.

Upgrade	★☆☆☆☆	★★☆☆☆	★★★☆☆	★★★★☆	★★★★★
Daze Increase	10%	11.5%	13%	14.5%	16%
Further Daze Increase	10%	11.5%	13%	14.5%	16%

Materials & Stats per Breakthrough Milestone (0 → 60)

The full ATK/sub-stat curve across all 7 milestones plus the materials each one costs, read straight from official data.

Lv.	Before	After	Material
Lv.0	ATK: - Impact: -	ATK: 40 Impact: 6%
Lv.10	ATK: 102 Impact: 6%	ATK: 138 Impact: 7.8%	Denny ×9,600 Stun Component ×3
Lv.20	ATK: 201 Impact: 7.8%	ATK: 236 Impact: 9.6%	Denny ×22,400 Reinforced Stun Component ×10
Lv.30	ATK: 299 Impact: 9.6%	ATK: 335 Impact: 11.4%	Denny ×48,000 Reinforced Stun Component ×16
Lv.40	ATK: 397 Impact: 11.4%	ATK: 433 Impact: 13.2%	Denny ×80,000 Specialized Stun Component ×8
Lv.50	ATK: 496 Impact: 13.2%	ATK: 532 Impact: 15%	Denny ×160,000 Specialized Stun Component ×16
Lv.60	ATK: - Impact: -	ATK: 594 Impact: 15%

Total materials for the full 0→60 climb

Denny ×320,000 Stun Component ×3 Reinforced Stun Component ×26 Specialized Stun Component ×24

Where To Farm

Combat Simulation — each Enemy Card costs 20 Battery, up to 5 cards per run (100 Battery for a full run).

Best Agents for this W-Engine

Recommended for

Dialyn S+

Ju Fufu S+

Koleda A

Lycaon S

How to Get This W-Engine

Pull it from Signal Search using Master Tapes / Encrypted Master Tapes (bought with Polychrome) — S-rank W-Engines get their own banner, usually alongside the matching character's banner.

Trade for it at the Gadget Shop's Box Galaxy section (Sixth Street): costs W-Engine Components + W-Engine Chips + Denny; Chips come from disassembling spare W-Engines.

A handful of A/B-rank W-Engines unlock through Proxy Primer trials or as story/event rewards instead of the gacha — not every W-Engine is pullable.

Compare with Same-Specialty Picks

Other Stun-specialty W-Engines, sorted by rank — solid stand-ins while you don't have the signature.

W-Engines	Rank	Base ATK (Lv.60)
Precious Fossilized Core	A	594
Chief Sidekick	S	713
Neon Fantasies	S	713
Yesterday Calls	S	713
Roaring Fur-nace	S	713
Spectral Gaze	S	713
Ice-Jade Teapot	S	713

Official Artwork / Lore

A special W-Engine whose outer shell is made of composite Etheric matter that effectively absorb incoming impacts in combat and turn it against the enemy. Rumors suggest that its prototype was crafted by a legendary Hollow explorer, and despite its ancient appearance, it continues to run smoothly. This W-Engine is literally an "old timer" in the field of W-Engines.

Alternatives of the same specialty

Stun specialty — decent picks while you don't have this one

Chief Sidekick

Neon Fantasies

Yesterday Calls

Roaring Fur-nace

Spectral Gaze

How to read this W-Engine page

Every W-Engine has 5 Refinement ranks (R1→R5): refinement ONLY strengthens the passive effect — the numbers in the table above run from left (R1, unrefined) to right (R5, max refinement via 4 duplicates or Overclock materials); Base ATK and the Advanced Stat (CRIT Rate/CRIT DMG/ATK%/PEN Ratio/Anomaly Proficiency...) do NOT change with refinement, only with the engine's level. "Best Agents for this W-Engine" prioritizes agents whose real build actually recommends this engine; if that data isn't available yet, the page falls back to agents sharing the same specialty as a rough guide. "Alternatives of the same specialty" lists other W-Engines with the same role — useful when you don't own the engine shown on this page.

FAQ

What is Precious Fossilized Core in Zenless Zone Zero?

Precious Fossilized Core is a rank A W-Engine built for the Stun specialty in Zenless Zone Zero — equip it on an Agent of the matching specialty to unlock the full passive effect; see the base stats and the full R1→R5 Refinement table in the sections above.

Which Agents should use Precious Fossilized Core?

Precious Fossilized Core fits Stun specialty Agents best, with 5 recommended characters including Koleda, Lycaon, Ju Fufu — see the full list with portraits in the "Best Agents for this W-Engine" section above.

How much Denny and material does it take to upgrade Precious Fossilized Core, and where do I farm it?

Leveling Precious Fossilized Core through every milestone takes roughly 4 W-Engine components and Denny ×320,000, Stun Component ×3, Reinforced Stun Component ×26 Denny combined — the components drop from Combat Simulation; see the exact breakdown per milestone and the Battery cost in the "How Much You Need" and "Where to Farm" sections above.

Is Overclocking Precious Fossilized Core worth it?

Overclocking only strengthens Precious Fossilized Core's passive effect from ★1 up to ★5 (5 copies) — it never changes Base ATK or the sub-stat, so getting the base copy matters far more; treat extra copies as a bonus.

Where do I get Precious Fossilized Core?

Mostly through Signal Search gacha (Polychrome); a few A/B-rank W-Engines are tradeable at the Gadget Shop's Box Galaxy or come from story/event rewards — see the "How to Get" section above for details.