Prior Extinction Fossil Discount Planner

The Fossil Discount Planner is a decision worksheet for Prior Extinction unlocks. Fossils reduce Amber prices on dinosaurs you do not own yet. Spending them early on a mid-tier you will outgrow can delay the apex you actually wanted. Use this page with live purchase-screen numbers, because Recode economy patches can retune rates.

Prior Extinction is Jacys Studios’ free Roblox dinosaur survival game (Place 6698800091). Community documentation commonly describes about 100 Amber discounted per Fossil on normal playables, about 50 Amber per Fossil on apex-tier bodies, and a soft cap near 75% of the list price. Your client’s preview is always authoritative—treat the math below as planning scaffolding.

Planner inputs

Write these down before you touch the Fossil button:

1. Target dinosaur from the Dinosaur Roster and Tier List.
2. List Amber price shown on the unowned card.
3. Fossils currently owned.
4. Normal vs apex tier (affects Amber-per-Fossil expectations).
5. Amber currently owned (after Codes and quests).
6. Whether you still need Fossils for a higher priority unlock later this month.

Quick estimate formulas

Use community-style estimates only until the UI preview confirms:

• Normal unlock Amber saved ≈ Fossils applied × 100
• Apex unlock Amber saved ≈ Fossils applied × 50
• Suggested max Fossils ≈ floor(0.75 × list Amber ÷ Amber per Fossil)
• Remaining Amber to earn ≈ max(list Amber − Amber saved − 0, 0) adjusted by the live preview

Example A — normal mid-tier listed at 5,000 Amber, you hold 20 Fossils:

• Estimated save 20 × 100 = 2,000 Amber
• Preview remainder ≈ 3,000 Amber (verify in UI)
• Decision: apply if 3,000 fits your bank; otherwise farm Amber first via how to get Amber.

Example B — apex listed at 20,000 Amber, you hold 80 Fossils:

• Estimated save 80 × 50 = 4,000 Amber
• 75% ceiling might stop earlier—stop when the preview refuses more Fossils
• Decision: if remainder still huge, keep caving with how to find Fossils before you soft-lock your wallet.

Decision rules

Apply Fossils when:

• The dinosaur is on your written unlock list.
• Remaining Amber after discount is reachable this week.
• You are not starving a higher-priority apex of Fossils.
• Mastery or roster plans say this body teaches skills you need (pounce and abilities).

Bank Fossils when:

• You are within a few caves of a better discount breakpoint on a dream apex.
• The current target is a novelty mid-tier you will abandon.
• Quest weeklies are about to pay a Fossil lump sum—wait two days.
• You still do not understand the species’ diet or combat role.

Session workflow

1. Redeem codes; note Amber.
2. Open quests; collect easy Fossil rewards.
3. Run one safe cave loop; bank.
4. Open this planner; compute remainder.
5. Open the dinosaur card; apply Fossils slowly while watching the preview.
6. Confirm purchase only if remainder Amber is already in your pocket or on tonight’s Amber route.
7. Log the spend so you do not double-count Fossils later.

Pair with the Amber planner and code checklist so Fossil math and Amber math share one night’s goal.

Radar and gamepass note

A Fossil radar gamepass can raise pickup rate but does not change discount formulas. Read Gamepasses before buying convenience. Scripts that auto-collect every node are unsafe—see Scripts.

Common planning errors

• Using outdated “100 per Fossil on apex” math—apex often discounts less per Fossil.
• Ignoring the 75%-style ceiling and wondering why the button greys out.
• Applying Fossils before checking Melanistic/Leucistic egg goals on Eggs and Skins when your real target was cosmetic, not unlock.
• Forgetting that applied Fossils are gone if you mis-click the wrong dinosaur.

Mini worksheet (copy to notes)

• Target:
• List Amber:
• Tier (normal/apex):
• Fossils owned:
• Fossils to apply tonight:
• Estimated Amber saved:
• Amber still required:
• Amber sources tonight (quests/caves/food loops):
• Go / wait decision:

When every line has an answer, Fossil spending stops feeling emotional. It becomes another Recode systems checklist—just like Wellbeing.

More tools and routes: Tools Hub, Growth and Mastery, Updates Hub, and Getting Started.