Mutant Carp★
The strange waters of the sewers have turned this carp into a monster. Its glowing eyes hint at unnatural mutations.
Quick answer
Where to catch Mutant Carp in Stardew Valley
Catch Mutant Carp at Sewers during Spring, Summer, Fall, Winter from Any in any weather. It sells for 1000g at normal quality and 2000g when smoked; difficulty 80 makes tackle preparation important.
Sewers
Spring, Summer, Fall, Winter
Any, any weather
1000g base, 2000g iridium
530g Roe -> 1060g Aged Roe
Cork Bobber or Trap Bobber
Sell extras; keep one for collection or Fish Pond use
Price decision
Sell, smoke, or use a Fish Pond?
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Sell directly
1000g
Normal quality
Smoke once
2000g
+1000g before Coal and machine time
One pond product
530g Roe → 1060g
Aged Roe; not daily profit
Is Mutant Carp worth keeping?
Keep Mutant Carp if it fills a bundle, recipe, gift, Fish Pond, or collection goal.
When to sell or smoke it
Sell or smoke extra Mutant Carp when you need gold and do not have a specific use for it.
Fish Pond and Roe
530g Roe can become 1060g Aged Roe. Fish Pond output depends on pond population and random daily production rolls. Formula value: 530g Roe, then 1060g Aged Roe.
Fish Pond output depends on pond population and random daily production rolls. The exact max-population output table and first capacity quest are shown below.
Verified 1.6.15 pond rules
Mutant Carp Fish Pond output
Final daily chances at population 1; each value already includes the pond's 50% base output check and ordered item rolls.
Any item per day
43%
Maximum population
1
Population growth
No reproduction
| Possible item | Quantity | Overall daily chance |
|---|---|---|
| Roe | 1-4 minimum | 43% |
Where & When to Find Mutant Carp
Location
- Sewers
Found only in the Sewers. Requires the Rusty Key from Gunther (donate 60 items to the Museum).
Time & Conditions
Difficulty & Catching Strategy
Difficulty: 80
HardChallenging catch requiring skill
Dart Behavior
Makes sudden, quick movements in random directions. Most unpredictable behavior.
Tip: Stay centered and use small, quick adjustments. Don't overreact to movements.
Expert Tips for Mutant Carp
While listed as difficulty 80, its darting behavior makes it unpredictable. The good news is it's available year-round and any time of day.
Recommended Tackle
Cork Bobber
Larger fishing bar
Best for: Hard fish like legendaries
Trap Bobber
Slower catch bar drain
Best for: Difficult fish that move a lot
Tackle requires an Iridium Rod. Purchase from Willy's shop at Fishing Level 6.
Sell Prices by Quality
| Quality | Price |
|---|---|
| Normal | 1000g |
| Silver | 1250g |
| Gold | 1500g |
| Iridium | 2000g |
Smoked Fish Value
The Fish Smoker uses 1 Coal and doubles the fish sell price while preserving quality. Fisher or Angler changes the fish value first; Artisan then increases the smoked product.
| Input Quality | Fish Value | Smoked Value |
|---|---|---|
| Normal | 1,000g | 2,000g |
| Silver | 1,250g | 2,500g |
| Gold | 1,500g | 3,000g |
| Iridium | 2,000g | 4,000g |
Formula: fish sell price x 2. See the formula audit for source notes.
Uses for Mutant Carp
- Legendary trophy fish
- High-value sale
Did You Know?
The Sewers location is unlocked by donating 60 items to the Museum, and also contains Krobus's shop.