You're standing on the edge of Roslit Volcano, your rod is shaking, and the tension meter is screaming. You pull in a fish. It glows. It sparkles. It’s got a weird tag next to its name. If you've spent more than five minutes in Fisch on Roblox, you know that the base fish is just the beginning of the grind. Getting a regular Trout is fine for a beginner, but the real endgame is hunting for every single Fisch mutation. These aren't just cosmetic flourishes either. They change how much money you make, how much XP you gain, and, most importantly, how massive that fish actually is.
Some people think it's all just random luck. It’s not. Well, mostly it's luck, but there are ways to tilt the scales in your favor.
What Exactly Is a Mutation Anyway?
Think of a mutation as a permanent modifier. When a fish spawns, the game rolls a dice to see if it’s standard or something "more." It’s basically the "Shiny" mechanic from Pokemon but applied to aquatic life. Most of these carry a weight or value multiplier. If you're trying to climb the leaderboard or just want to afford that expensive Kraken rod, you need to understand that the Fisch mutation system is your best friend. Or your worst enemy, depending on how many thousands of casts you've done without seeing a Midas.
The Common Mutations You’ll See Every Day
You’re going to see these a lot. They aren't game-breakers, but they help the grind feel a bit faster.
Big. This is the bread and butter of mutations. It increases the weight of the fish by about 1.1x to 1.5x. It's a simple buff. Nothing crazy. You'll get a bit more cash for it when you sell it to the merchant. Small is the opposite. It’s a bit of a slap in the face, honestly. It reduces the weight. If you're trying to break a server record, seeing "Small" pop up is basically the game telling you to try again.
Then you have Sparkly. You’ll notice these immediately because of the particle effects. They give a nice little 5% to 10% boost to the sell price. It’s not much, but over a long fishing session at Terrapin Island, it adds up.
The Ones That Actually Matter for Your Wallet
Now we’re getting into the stuff that makes the grind worth it. Shiny is the one most players aim for early on. It’s a 2x multiplier on the value. If you catch a Shiny Great White Shark, you're looking at a massive payday. It also gives a decent XP boost.
But Golden? That’s better.
A Golden mutation adds a 3x multiplier to the value. The fish literally glows yellow in your inventory. It’s one of the best ways to farm cash in the mid-game.
The Rarest Mutations in Fisch
If you see these, take a screenshot. Seriously.
- Midas: This is the king of value. It turns the fish into solid gold. We’re talking a 5x value multiplier. If you get a Midas mutation on a rare legendary fish, you’ve basically won the lottery for that session.
- Albino: This one is mostly for the collectors. It turns the fish white and gives it red eyes. It provides a decent weight boost, but people mostly want it because it looks cool in the Bestiary.
- Negative: This is a weird one. The colors are inverted. It looks ghostly. It’s significantly rarer than Shiny or Golden, and while the value isn't quite as high as Midas, the rarity makes it a huge flex.
- Mythical: This is the pinnacle. The drop rate is insanely low. It gives a massive 10x multiplier to value and a huge boost to weight. Most players will go their entire career without seeing a Mythical variant of a rare fish.
Why Your Luck Feels Terrible (And How to Fix It)
Most players just throw their line into the water and hope for the best. That’s a mistake. If you want to see a specific Fisch mutation, you need to use the right bait and the right rods.
For example, the Magnet Rod is great for items, but if you're hunting mutations, you want something with a higher "Luck" stat. The Luck Rod or the Heavenly Rod are the gold standards here. Also, keep an eye on the weather. Some mutations seem to have a higher "roll" chance during specific global events or weather patterns, though the developers keep the exact percentages pretty close to the chest.
Bait also matters. Enchanted Bait or Weird Bait can drastically increase the chances of the game rolling for a mutation rather than a standard fish. If you're just using worms, don't be surprised when you catch 500 normal Cod in a row.
The "Secret" Mutations and Visual Variants
There are a few modifiers that people argue about whether they count as "true" mutations or just size modifiers. Colossal and Giant fall into this camp. They aren't technically mutations in the same way "Midas" is, but they affect the weight so much that they function the same way for your XP bar.
A Colossal fish can be up to 2x the normal weight. If you're fishing in the Deep Sea, catching a Colossal version of a deep-sea creature is the fastest way to level up your character.
Handling the "Glitch" Mutation
There has been a lot of talk in the community about the Glitch mutation. It’s incredibly rare and gives the fish a digital, pixelated aura. It doesn't just increase value; it provides a massive boost to the XP you get for catching it. It’s widely considered the rarest visual effect in the game currently.
How to Optimize Your Mutation Farm
If you want to actually fill out your Bestiary with every Fisch mutation, you have to stop fishing randomly.
First, pick a spot with a high "Legendary" spawn rate. The Sunken Ship or the Blue Hole are great. Use a rod with a high Luck stat—ideally the Mythical Rod if you can afford the grind to get it. Then, stack your buffs. If there is a server-wide luck event happening, that is the only time you should be using your high-tier bait.
Don't waste your Weird Bait on a Tuesday afternoon when nothing is happening. Wait for the luck multipliers.
Also, pay attention to the "Weight" of your line. Some mutations are actually locked behind certain weight thresholds. If your rod can't handle the weight of a Colossal variant, the game might not even roll that mutation for you. It’ll just cap it at a lower tier.
The Economics of Selling Mutations
A mistake I see all the time: selling Midas or Shiny fish to the standard merchant immediately.
Check the Fish Market boards first. Sometimes there are daily quests or specific NPC demands for mutated fish that will pay way more than the base merchant price. If an NPC wants "3 Shiny Fish," and you give them three Shiny Sharks, the reward multiplier can be astronomical compared to just dumping them in the sell bin.
Actionable Steps for Hunting Mutations
To maximize your chances of hitting those high-tier rolls, follow this progression:
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- Upgrade your Rod immediately: Move from the Carbon Rod to the Luck Rod as soon as you have the cash. The 10% or 20% luck buff doesn't sound like much, but it applies to every single cast.
- Save your Weird Bait: Only use it in high-value zones like the Roslit Volcano or the Moosewood secret spots during rain or fog.
- Check the Bestiary: See which fish you are missing. Some mutations are easier to get on "Common" fish. If you just want the achievement, grind out Common fish in the starting pond to "force" the mutation rolls.
- Join a Pro Server: Look for servers where people are using Luck Potions or Luck Totems. These buffs often have a radius or a server-wide effect that you can piggyback off of.
- Manage Inventory: Don't auto-sell everything. Keep one or two high-value mutations (like Golden or Midas) to show off or to turn in for high-tier quests that might pop up.
The grind for every Fisch mutation is a marathon, not a sprint. You might go three days without seeing anything better than a "Big" Trout, and then hit a Mythical Hammerhead on a random Tuesday. That's just the nature of the sea. Keep your line in the water and watch the weather.