Be a Fish Bait Mutations

By Jim Liu · Last updated 2026-07-17

All 8 Be a Fish Bait mutations, the multiplier each one carries, how to unlock it, and a calculator that stacks Radioactive, Delulu, and Champion the way the game actually does.

TL;DR

8 mutations exist as of the Delulu Update. Radioactive is the strongest at 8x, Gold the weakest at 1.5x.
A fish can carry one Normal mutation plus both Special mutations (Delulu, Champion) at once - never two Normal mutations.
Delulu and Champion stack additively, not multiplicatively - a Radioactive x Delulu x Champion fish is 13x (8+2+3), not 48x.
Already caught a mutated fish? Plug your combo into the calculator for the exact cash value.

All 8 Be a Fish Bait mutations, ranked by multiplier

Six of these are Normal mutations - only one can land on a fish at a time. Delulu and Champion are Special mutations that layer on top of a Normal mutation instead of replacing it, which is why they're marked separately below.

Mutation	Type	Multiplier	How to get it
Radioactive	Normal	8x	Random catch on any cast (RNG, no weather or fish type required)
Molten	Normal	6x	Random catch on any cast (RNG, no weather or fish type required)
Glitched	Normal	5x	Fish during Glitched weather (+10% catch chance while it lasts)
Plasma	Normal	4x	Random catch on any cast (RNG, no weather or fish type required)
Champion	Special	3x	30% chance whenever you hook a Boss Fish
Diamond	Normal	2x	Random catch on any cast (RNG, no weather or fish type required)
Delulu	Special	2x	Fish during Delulu weather
Gold	Normal	1.5x	Random catch on any cast (RNG, no weather or fish type required)

Mutation stack calculator

Pick the Normal mutation your fish landed, tick on Delulu or Champion if it also has one, and drop in what the fish is normally worth to see the real aquarium payout.

Normal mutation on this fish

+ Delulu (2x, Delulu weather)+ Champion (3x, 30% on Boss Fish)

Base cash value of this fish (before mutations)

Total multiplier

A 100 cash fish with this exact combo is worth 100 cash once it hits your aquarium.

Multipliers add on top of each other here, not multiply - matching the game's own "stacks additively" rule for Delulu and Champion. The full 8-mutation table with unlock methods is below.

How mutation stacking actually works

Every fish starts at its base cash value with no mutation, which is the same as a 1x multiplier. Landing a Normal mutation replaces that 1x with the mutation's own multiplier - there is no case where a fish carries two Normal mutations, since getting a second one just means the fish rolled a different outcome. Delulu and Champion don't follow that replace-the-multiplier rule, though. They're Special mutations that stack on top of whatever Normal mutation (or lack of one) the fish already has.

The stacking itself is additive, not multiplicative - the game adds the extra multiplier values together rather than multiplying them. That matters more than it sounds: a Radioactive fish that also picks up Delulu and Champion comes out to 8 + 2 + 3 = 13x, not 8 x 2 x 3 = 48x. It's still the best combo in the game by a wide margin over a plain 8x Radioactive, just not the eye-watering number multiplicative stacking would produce.

One honest gap: neither Pro Game Guides nor the community wiki has published the Radioactive x Delulu x Champion combo as one official combined number - what they do confirm is the additive stacking rule, which is what the calculator above applies. If a future update changes that to multiplicative stacking, this page and the calculator would both need an update.

Boosting your mutation odds

Clicking the pop-up buttons that appear on screen when you throw the bait raises your general chance of landing a mutation on that cast - it's a small, easy-to-miss window, and skipping it is the main way players leave mutation rolls on the table. Weather events layer a second boost on top for specific mutations: fishing during Glitched weather adds +10% catch chance for the Glitched mutation, and Delulu weather is what makes the Delulu mutation catchable in the first place.

Two auras, Yinyang and Voidspore, are also described as giving a mutation luck boost. We couldn't find a published percentage for either one, so treat them as a nice-to-have on top of a good aura roll rather than something worth chasing purely for the mutation angle - the exact odds math on the reroll calculator only covers aura rarity, not this mutation boost.

See a mutated catch in action

The multipliers above are the theory - here's a real Extinct-rarity run where a mutated catch actually lands, aura pull included.

Where this comes from

The 8 mutations, their multipliers, and the unlock methods above were checked against Pro Game Guides' Delulu-update mutations writeup and the current community wiki before publishing, the same standard our other pages use for anything we didn't catch ourselves in a live session. Where a number wasn't published anywhere we could find - the Yinyang and Voidspore luck boost percentages, mainly - this page says so instead of guessing.

FAQ

What is the best mutation in Be a Fish Bait?

Radioactive - it's the highest Normal mutation multiplier in the game at 8x, ahead of Molten (6x) and Glitched (5x). It's a random catch like the other five Normal mutations, so there's no weather window or fish type that guarantees it.

How do you get the Radioactive mutation?

Random catch on any cast - Radioactive doesn't require a specific weather event or Boss Fish the way Delulu and Champion do. Clicking the pop-up buttons that appear when you throw the bait raises your odds of landing a mutation in general, Radioactive included, but the mechanic is still RNG underneath.

What does the Delulu mutation do?

Delulu is a 2x Special mutation you can only catch during Delulu weather, and unlike the six Normal mutations it stacks on top of whatever Normal mutation the fish already has instead of replacing it. A fish can carry a Normal mutation and Delulu at the same time.

How do you catch a Champion mutation fish?

Champion only rolls on Boss Fish, at a 30% chance each time you hook one - it doesn't spawn on regular catches at all. Like Delulu, it's a Special mutation, so it stacks additively on top of a Normal mutation rather than needing to replace one.

Can a fish have two mutations at once in Be a Fish Bait?

Yes, but not two Normal mutations. A single fish can carry one Normal mutation (Gold, Diamond, Plasma, Glitched, Molten, or Radioactive) plus both Special mutations (Delulu and Champion) at the same time, for up to three mutations stacked on one catch.

What's the highest possible mutation combo?

Radioactive x Delulu x Champion - the developers confirm this is the peak combo but haven't published one combined number for it. Since Delulu and Champion are stated to stack additively rather than multiplicatively, the calculator above adds the three multipliers together (8 + 2 + 3 = 13x) instead of multiplying them.

Do Yinyang and Voidspore auras affect mutations?

Both are described as giving a mutation luck boost, on top of whatever aura effects they already have from the reroll system. Neither the exact percentage nor how it stacks with the Glitched-weather bonus is published anywhere we could find, so treat them as 'helps your odds' rather than a number you can plan around.

What does Glitched weather do?

It raises your catch chance for the Glitched mutation specifically by +10% while the weather event is active - it doesn't touch the odds of the other five Normal mutations or either Special mutation. Delulu weather works the same way but only for the Delulu mutation.