Mechanics

Everything is Crab Mutagen Guide: Rerolls, Rarity, Endless Value

By Nocti · Last updated

Mutagen questions are really pacing questions: when to reroll early, when to hold upgrades for rarity, and why Endless runs can end up with spare mutagen after the build is already solved.

Practical use

  1. Spend mutagen to protect the current route problem, not because the total looks large.
  2. Early and mid game rerolls are strongest when they preserve one damage family, food engine, or boss-safe movement line.
  3. A fresh July 3 Extinction 43 record is a useful reminder that risky openers only pay when the mutagen spending later pivots the shell into something safer instead of forcing the same high-roll plan forever.
  4. If a nearly finished evolution matters long term, holding it until you can also raise rarity can be better than clicking the upgrade immediately.
  5. Simple, Patient, and similar control starts trade early tempo for cleaner later offers; use them when route control matters more than raw opening power.
  6. In Endless, spare mutagen usually means the build identity is already finished, so stop reading the number as automatic power and start looking for caps, survivability, and better POI usage instead.

Mutagen route map

QuestionAnswer firstUse it this way
When should I reroll early?Reroll when the offer would split your damage family or leave food and movement unsolved.Protect the route shell before spending on luxury upgrades.
Should I hold points for rarity?If a near-finished evolution is core to the run, waiting until you can also raise rarity can be stronger than clicking it immediately.Use this mostly on long or Endless-leaning runs, not on unstable openings.
Are Simple or Patient always strong?No. They are control tools that trade early tempo for cleaner later offers.Take them when route quality matters more than raw opener power.
Why does Endless mutagen feel weak?Late Endless often gives more mutagen after the build identity is already finished.Once that happens, look for stat caps, survivability, and better POI use instead of treating the mutagen total as hidden damage.

Recent public discussion now spans both late-Endless mutagen overflow and videos built around mutagen farming. The practical question is not how high the number can go, but whether more mutagen still changes the route.

Related pages

Reroll Picky

A route for reroll-heavy unlock farming, build fishing, and learning how mutagen spending changes level-up decisions.

Read guide

Endless: unlocking and continuing a run

Win at Pressure 10 or higher, then choose Endless on the victory screen. Learn why the button can be disabled, how to save a long run, and what Extinction results tell you about survival.

Read guide

Reroll and Mutagen Cases

Compare public cases to see when mutagen protects the route instead of only inflating the total.

Read guide

Everything is Crab Build Planner

Choose evolutions, arrange a route, compare card composition and preview body parts and scenery; share a link or export an image.

Read guide

Know which action is using the currency

A reroll changes the offered choices; a rarity purchase changes their tier; skipping a Specialisation is a separate decision. Version 1.1 added a ten-Mutagen reward for skipping a Specialisation. It does not follow that every skipped choice, every level-up or every closed menu gives the same reward. Read the control and its displayed result before counting it toward a spending plan.

FAQ

Why can two starting Genetics have different Mutagen budgets?

The same update raised Simple’s starting Mutagen to 200 and increased Stubborn’s Mutagen from Rare and Epic choices. The Stubborn patch entry does not specify exact payouts. Use those changes to understand why two starts can have different budgets, while relying on the actual displayed balance for a purchase. A historical screenshot from another Genetic is not your available currency.

Source

A spending decision with a visible stopping point

  1. Name the missing function before opening another offer: a way to apply damage, a way to move out of danger, food access or a particular requirement for the chosen objective.
  2. Compare the current usable offer with that function. If it already solves the problem, explain what another reroll is expected to improve rather than spending solely because the balance is high.
  3. Read the current purchase cost and retain enough currency for any other action you are deliberately planning. Do not use a quoted opening cost as proof that later purchases have the same price.
  4. Stop reassessing the same ideal build once the actual run has changed. A newly acquired movement tool or a different food route can make yesterday’s desired card optional.

FAQ

Does more Mutagen always mean more damage?

No. Currency is useful through the choices it buys. If an offer cannot improve the part of the route that is failing, a larger balance does not by itself fix that failure. In a long run, inspect the actual next upgrade and any relevant stat cap.

Should I count rarity purchases as rerolls?

Keep the actions separate. The 100-reroll objective and Elitist’s 20 upgrades name different operations. A total amount spent cannot establish how many of either action occurred; use the relevant in-game progress rather than converting currency into an assumed counter.

Source

Update history

: Separated rerolls, rarity purchases and Specialisation skips; added Simple’s starting amount and Stubborn’s non-numeric patch change. Explained spending decisions without converting currency into achievement counts.