Fish mutations can trigger when you harpoon
Harpoon a Fish fish mutations can trigger when you harpoon a fish, according to FirstTry's official 2x Luck pass description. That pass advertises doubling the chance of triggering a mutation. This confirms both the connection to harpooning and a specific paid modifier, without establishing a guaranteed result on any catch.
The official Roblox pass listing for Harpoon a Fish is the source for those details. The listing was checked on October 17, 2026 and belongs to the same FirstTry game universe as Harpoon a Fish.
What 2x Luck actually advertises
The pass description connects its luck bonus directly to mutation chance when harpooning. It does not describe a two-times fish-size bonus, a guaranteed rare species, or a two-times cash multiplier.
| Detail | Official listing at the source check |
|---|---|
| Pass name | 2x Luck |
| Advertised effect | Doubles the chance of triggering a mutation when harpooning a fish |
| Listed price | 199 Robux |
| Sale status | For sale |
| Base mutation chance | Not supplied |
A doubled chance is a relative increase. Without a published base chance, it cannot be converted into a verified percentage or a fixed number of catches needed. It also does not mean that every second fish must mutate.
Check the current Roblox purchase prompt before buying, since price and availability may change. The listing supports describing the advertised benefit; it is not a personal test of the pass or evidence of how it combines with other possible bonuses.
Keep mutation goals separate from unsupported lists
The confirmed action associated with mutations is harpooning fish. If mutations are your goal, continue using that catching mechanic and check the game for the result of each completed catch. If you are considering 2x Luck, compare its specific mutation-chance benefit with what you want from the purchase.
The official material available here does not give a mutation-name catalog, individual mutation rates, sale-value multipliers, or a way to choose a particular mutation. It therefore cannot support a ranked mutation list or a guaranteed farming route.
Fish evolution is also advertised in the game's description, but the sources do not establish that evolution and mutation are interchangeable. A system that grows or evolves a fish should not automatically be treated as a verified way to apply a mutation.
Be especially careful with guides for the separate Roblox game Fisch. Its rods, mutation names, and quest requirements do not establish mechanics for FirstTry's Harpoon a Fish, even when both games use fishing terminology.
FAQ
How do fish mutations happen in Harpoon a Fish?
The 2x Luck description states that a mutation can trigger when you harpoon a fish. It does not publish the base percentage.
Does 2x Luck guarantee a mutation?
No guarantee is stated. The advertised effect is double the chance, not a mutation on every catch or every other catch.
How much does the mutation luck pass cost?
The official listing checked on October 17, 2026 showed 2x Luck for sale at 199 Robux. Confirm the current price in Roblox before purchasing.
What are the mutation names and value multipliers?
Those details are not established by the official sources used here. A complete table would need additional exact-game evidence rather than names or multipliers borrowed from another fishing game.