Steal a Brainrot Radioactive Mutation Update: Fishing & Trading (Release Info)

Steal a Brainrot Radioactive Mutation Update drops on November 16, 2025, at 3 PM EST. This massive update brings glowing green mutations, a new fishing event, and the ability to trade your existing Brainrots for fresh ones. If you’re ready to level up your Brainrot collection, here’s everything you need to know about this exciting release.

Steal a Brainrot Radioactive Mutation Update

Radioactive Mutation Event Start and End Times by Country

The Radioactive Mutation Event officially launches on Saturday, November 16, 2025, at 3 PM EST. The event runs until November 21, 2025. That gives you nearly a week to explore the new features, fish for aquatic Brainrots, and test out the trader system.

What is the Radioactive Mutation?

The Radioactive Mutation is a brand-new mutation type that transforms your Brainrots with a green radioactive glow. Like other mutations in the game, this one changes how your characters look and can boost the money they generate every second. The radioactive effect gives Brainrots a sharp, glowing appearance that stands out from the standard Gold, Diamond, and Rainbow mutations already in the game.

This update also includes a Radioactive spin wheel where you can try your luck. The spin wheel comes with a hidden radioactive secret block and new gear items to unlock. Players who collect all radioactive Brainrots will earn the Radioactive Index, a special achievement for dedicated collectors.

The New Brainrot Trader System

One of the biggest features in this update is the Brainrot Trader. For the first time, you’ll be able to trade your existing Brainrots for new ones directly through an in-game trader. This system lets you swap out characters you don’t want for a chance at better or rarer Brainrots.

The trader restocks every 2 hours with fresh offers. That means you’ll need to check back regularly if you want to snag the best deals. Whether you’re trying to complete your collection or just want to refresh your lineup, the trader gives you more control over your Brainrot roster.

Fishing Event Details

The Fishing Event runs every hour and lets you fish for Brainrots. During the event, you’ll cast your line and try to reel in rare aquatic-themed characters. The better your fishing rod, the more luck you’ll have landing valuable catches.

This event introduces the Aquatic Index, a new collection challenge. If you manage to collect all the aquatic Brainrots available through fishing, you’ll unlock this special index badge. The hourly schedule means plenty of opportunities to participate, so make sure to log in regularly during the event window (November 16 to November 21, 10:30 PM IST).

New Brainrots Coming in This Update

The update adds three exciting new Brainrots to the game:

• Centrucci Nuclucci (Mythic): This mythic-tier Brainrot is one of the rarest additions to the update.

• Swag Soda (Secret): A secret-rarity character that you’ll need to hunt down through special methods.

• ??? (Secret): A third secret character is coming, but the developers haven’t revealed its identity yet.

These new characters add fresh targets for collectors and could offer powerful multipliers depending on their traits and mutations.

How Mutations Affect Your Earnings

Mutations in Steal a Brainrot multiply the cash your characters generate per second. For example, Gold mutations give a 1.25x multiplier, while Rainbow mutations boost earnings by 10x. The Radioactive Mutation will likely follow this pattern with its own multiplier value.

If you combine mutations with traits from admin events, you can stack multipliers for even bigger profits. The formula is simple: multiply your Brainrot’s base earnings by the sum of your mutation and trait multipliers. With the right combination, you could be earning massive amounts of cash every second.

Tips for Making the Most of This Update

• Start by upgrading your fishing rod before the hourly fishing events begin. Better rods increase your luck and help you land rarer aquatic Brainrots faster.

• Check the Brainrot Trader every 2 hours for new offers. The restocking schedule means you’ll have multiple chances throughout the day to trade for characters you want.

• Focus on collecting all aquatic Brainrots during the fishing event to unlock the Aquatic Index. This badge proves you’ve mastered the fishing challenge.

• Try your luck at the radioactive spin wheel to unlock the secret block and new gears. These items could give you an edge in future updates or help you earn more cash.

Why This Update Matter

The Radioactive Mutation update is one of the biggest content drops for Steal a Brainrot in months. The addition of trading gives players more flexibility with their collections, while the fishing event adds a fun new activity to break up the usual gameplay loop. With three new Brainrots, a fresh mutation type, and limited-time events, there’s plenty of reason to jump back into the game this weekend.