If you’ve unlocked the Blue Moon area in FISCH and are now wondering how to complete the entire bestiary, you’re in the right place. This How To COMPLETE The Blue Moon Bestiary & Fish Location guide breaks down every fish you need to catch, including the rare and secret species, so you can finish the collection without missing a beat.
How To COMPLETE The Blue Moon Bestiary & Fish Location
What Is the Blue Moon Bestiary?
The Blue Moon Bestiary is a collection log that tracks all the exclusive fish you can catch during the Blue Moon Event. Completing it not only gives you bragging rights but also helps you earn more XP and understand the rarity tier of each fish.
All Blue Moon Fish – Full Bestiary List
Here’s the complete list of all the fish you need to catch to complete the bestiary:
Common to Uncommon Blue Moon Fish:
- Gloomfin Carp
- Moon Veil Killifish
- Lurking Crescent Pike
- Moonridge Catfish
- Crescent Madpom
These are relatively easier to catch once you’re inside the Blue Moon zone. If you’re not seeing some of them spawn, try moving between Sea 1 (Snowcap Island) and Sea 2 (Lush Grove) Blue Moon areas — some fish may be exclusive to one sea or have higher spawn rates in one.
Rare & Secret Blue Moon Fish:
Lantern Gobby (Rare)
- Found deep in the Blue Moon zones
- Low spawn rate; may take a few tries
Tarnished Moongill (Rare)
- Usually appears during the later phase of the event
- Keep fishing near glowing spots
Moon Idol C2 (Secret Fish)
This one is mysterious and has confused many players
The game hints that it’s connected to a moon-shaped stone with unmatched spirit
May require a special item or area to trigger its appearance (keep an eye out for hidden clues or interactables in the map)
The Moon Idol C2 is the most mysterious fish in this update. The in-game description mentions a moon-shaped stone with unmatched spirit, which may hint at:
A secret interaction or object you need to find
A specific time during the event
Or even a quest tie-in
Keep experimenting and exploring, especially around Lush Grove’s Blue Moon zone. If you find something unique, cast your line — you might just unlock this elusive catch.
Tips to Complete the Bestiary Faster
Switch Between Sea 1 and Sea 2: Some fish might only spawn in one sea’s Blue Moon zone.
Use Better Rods: Even though the update didn’t introduce a new rod, using the highest tier rod increases your chances for rare and secret catches.
Look for Visual Cues: Glowing pools, bubbling spots, or out-of-place scenery might hint at rare fish spawn points.
Stay Through the Whole Event: Rare fish tend to spawn later into the Blue Moon event, so don’t leave early.