The Atomic mutation is a powerful upgrade for any fish because its sell value gets multiplied by 8x. Visually, the fish takes on a bright neon-yellow glow with some particle effects, making it one of the most standout creatures in your collection. So, if you’d like to know the location, weather, season, time and bait to get these types of fish in your bestiary, our guide will walk you through the steps.
How to Get Atomic Mutated Fish in Fisch

To get the Atomic mutation, there’s no specific weather condition you need to track. The only thing you need is an item called the Atomic Nuke, which will trigger an event. Here’s how it works:
Obtaining the Atomic Nuke
You can find an Atomic Nuke while fishing in any body of water in the First Sea, but the chances are extremely low (~1 in 75,000). If you have the Scavenger enchantment on your rod, that rate improves to about 1 in 50,000. You can also purchase one from the Black Market for 10,000,000 C$.
Activating the Event
Once you get the Atomic Nuke, you’ll enter a minigame to balance it.
If you succeed the minigame: You keep the Atomic Nuke as an item in your inventory for later use.
If you fail the minigame (or choose to detonate instead): The Atomic Nuke explodes and creates a special area around you. Inside that explosion radius, any fish you catch will have the Atomic mutation applied and so, they will get the 8x value boost.
For the duration of the active event in that zone, any fish caught within that radius will receive the Atomic mutation. After the event ends, the effect goes away, and you’ll need another Nuke to repeat it.
If you plan to sell, trade, or show off your fish, having multiple with the Atomic mutation will be very useful.
Tips and Tricks
Always fish with the Scavenger enchantment active if you’re hunting for the Atomic Nuke because it gives you a 3x higher chance to catch Nukes, Enchant Relics, Treasure Maps and Threads. Plus, you get a 1.75x higher chance for Exalted Relics and 1.5x higher chance for Atomic Nukes.
Prepare your best fishing rod before entering the event zone so you’re ready to reel in high-value catches quickly once the explosion happens. This includes the rarest catch – the Skeletal Serpent.
Coordinate with friends or group members because detonating the Nuke in a populated server can mean more fish caught by your team under the Atomic bonus.
FAQs about the Atomic Nuke Event
Q1: Can I use any fishing spot for the Atomic Nuke event?
Yes, since the Atomic Nuke can spawn from any body of water in the First Sea, you’re not restricted to special locations.
Q2: Will all fish caught in the zone instantly get the Atomic mutation?
Only the ones caught within the radius after the Nuke detonation will gain the mutation.
Q3: Does the Atomic mutation last forever on the fish once caught?
Yes, the mutation is permanent for that fish, so its boosted value is maintained.
