Get the Rain Mutation
Server
23
Global
86
The rain run in the October 14, 2026 recording mutated pets already standing in the pen and printed the notice below.
Sep 1 and Oct 14, 2026 recordings
My Billionaire Zoo Mutations and Weather Costs
A mutation is a named change the game puts on a pet you have already placed, and weather is the only way the recordings show it arriving. Here are the printed prices, the notice to watch for, and the 25-Gem item that erases one. Checked October 28, 2026.
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Mutations: weather puts a name on a pet, and the panel already prints what it costs
What it is: a named variant the game attaches to a pet that is already placed in your pen, announced in chat as Your Parrot got the Rain mutation!
Printed prices: Rain 23 Server / 86 Global, Alien 54 Server / 189 Global on the Weather panel read September 1, 2026. Tsunami sits under them with its prices below the frame edge.
Erasing one: the Gem Shop sells a Pet Cleanser for 25 Gems, described as "Erase pets of their mutations, allowing you to get new better ones!" and marked one time use.
What is still missing: the cash-per-second multiplier. No checked recording keeps a readable label on the same pet before and after the event, so this page shows you where to read it instead of printing a number.
The panel
Three weathers, two prices each
One card per row of the Weather panel, with the numbers exactly as they were printed. Rain was also seen running live; the other two were only seen as prices.
Get the Alien Mutation
Server
54
Global
189
More than double Rain on both buttons. No checked recording shows the Alien event actually running or the look it leaves on a pet.
Sep 1, 2026 recording
Get the Tsunami Mutation
Server
not read
Global
not read
The third row was cut off at the bottom of the panel frame, so its two prices were never on screen in the frames checked.
Sep 1, 2026 recording
The two buttons are labelled Server and Global on the panel itself. Nothing on screen explains what the second price buys, and no recording pays both. Treat the pair as two ways to summon the same weather until your own panel says otherwise.
Sequence
Run it in the order that does not waste the payment
Five steps. The last two are the ones that decide whether the mutation was worth buying.
1
Fill the pen before you pay for weather
The event mutates pets that are already placed in the pen. Anything still sitting in the backpack is not in the pen when the event fires, so place and keep the pets you want changed before you pay.
2
Open the Weather panel and read both buttons
Each row prints two prices side by side, one under the label Server and one under the label Global. The icon on those buttons is not the blue diamond the Gem Shop prints beside its 25, so the cards above repeat the numbers without naming a currency.
3
Watch the notice instead of the sky
The mutation is announced in the chat area: Your Parrot got the Rain mutation! That line is the confirmation that a specific pet changed. The October 14, 2026 recording shows it twice in the same second for the same pet.
4
Read the pet's own cash label before and after
A placed pet shows its own cash per second. That label is the only place the size of the change can be read, and no checked recording kept a clean before-and-after pair, so this page does not print a multiplier.
5
Keep it, sell the pet, or cleanse it
A mutation you do not want is cleared with the Pet Cleanser from the Gem Shop for 25 Gems. Cleansing is worth it only on a pet you intend to keep: the Sell stall pays a fixed price per pet in the recordings, and none of them shows a mutation raising what a sale returns.
Decision
Cleanse, keep, or sell
25 Gems is the only mutation price on this page that comes with a named currency.
Cleanse: worth it on a pet whose rate you are relying on and whose look you do not want. The item is one time use, so budget 25 Gems for each pet you decide to clear.
Keep: no checked recording measures a mutation lowering a rate either, so nothing observed yet says a bad mutation is a loss. Measure it before spending Gems on it.
Sell: the Sell stall pays a fixed price per pet — $15 for a Dog, $5K for a Capybara in the October 14, 2026 recording, read on pets with no mutation noted. Cleansing a pet you are about to sell spends 25 Gems on a pet that leaves the pen.
Price anchor: 25 Gems is one sixth of the 150 Gems that buy a Snail at 1.25x your current best pet. That comparison is the real decision: a cleanser reroll versus a guaranteed pet.
Honest gaps
What no recording has settled
These stay open on the page rather than filled in with a guess.
The multiplier: unread. The notice fires, the model changes, and the cash-per-second label on that pet was not captured cleanly before and after in either recording.
Persistence: the Pet Cleanser exists to erase mutations, which is why this page treats a mutation as something that stays until removed — but no recording watches one across a rebirth, a rejoin, or a weather change.
Stacking: whether a second weather overwrites the first or adds to it was never shown. Rain was the only event that ran in a checked session.
The look: the Rain frames read for this page show the announcement clearly but not a clean repaint of the pet, so no appearance is described here for Rain.
Build currency: the panel was read in the September 1, 2026 recording and the event in the October 14, 2026 recording. The official update date has since moved to October 16, 2026, and no recording covers that build, so read the panel wording and prices on your own screen.
FAQ
Frequently asked questions about mutations
Where mutations come from, what they cost, how to remove one, and what remains unmeasured.
How do you get mutations in My Billionaire Zoo?
Through weather. In the September 1, 2026 recording the Weather panel lists Rain, Alien and Tsunami, each row naming the mutation it applies, and the October 14, 2026 recording shows a Rain event running on a live pen and announcing the change per pet. No recording shows a mutation arriving any other way.
How much does it cost to trigger a weather mutation?
Each row prints two prices: Rain 23 Server and 86 Global, Alien 54 Server and 189 Global. Tsunami's prices were cut off in the frame. What the Server and Global buttons buy differently was not shown, and the price icon is not the blue gem the Gem Shop uses, so these are the printed numbers rather than a gem price.
How much cash per second does a mutation add?
No checked recording shows the number. Both sessions show the notice firing, but neither keeps a readable cash-per-second label on the same pet before and after, so this page does not claim a multiplier. Read your own pet's label immediately before and after the event and the difference is on your screen.
How do you remove a mutation?
Buy the Pet Cleanser in the Gem Shop for 25 Gems. Its panel text reads: Erase pets of their mutations, allowing you to get new better ones! It is marked one time use, so price it against the pet, not against the whole zoo.
Is a Gold pet the same as a mutated pet?
No. Merge turns 5 identical pets plus 50 Gems into a gold version with a doubled rate on that pet, and that is a separate building. A mutation is the weather-applied change that the Pet Cleanser targets. The two are read from different panels in different recordings.
Do mutations survive a rebirth?
Not confirmed. A rebirth takes the placed animals back, and no checked recording re-reads a mutated pet after a reset. Assume nothing until you see it on your own account, and do not pay for weather immediately before a rebirth.
Index, Merge, Fuse and Weather
Where weather sits among the other systems that change a rate.
IncomeCash Rate Levers
The four levers that move cash per second, and what each one costs.
ItemsGem Shop and Sell Prices
What 25, 150, 450 and 1,500 Gems buy, and what the Sell stall pays back.