If you are after the Silly Fun Happy Rod in Fisch, along with the 20 Balloon Animals, you must also try to get the String to make it fly, as per the wish of the Clown NPC. Here is a brief guide to quickly getting the String in Fisch and the Silly Fun Happy Rod.
Where is the String available in Fisch?
The String is a fishable item in Fisch that players can catch in the Desolate Deep. You can reach Desolate Deep by using the Advanced Diving Gears + Flippers from the Buoy near the Sunstone Island at (-790, 125, -3100). After diving, take the left tunnel to reach the Desolate Pocket, where you can catch the String.
How to catch the String in Fisch

Since the item is trash-tier, players can use the Magnet Bait and something like the Training or the Flimsy Rod. Though it does prefer any bait, the Magnet Bait with a low luck will inform the system that the player is looking for something with the Trash category, helping you speed up the process. Also, there are no specific season, time, or weather requirements for the String, making it even easier for you. That's it! Keep fishing until you get the String in Fisch.
What is the use of String in Fisch?
Apart from giving the item to the Clown to get the Silly Fun Happy Rod, the String has no other use in Fisch. In fact, the player will receive random messages like "Seems Pointless" or "CURSE YOU POLARIS!" while fishing a String. Hopefully, the developers will add the item as one of the ingredients that a player must obtain to get one of the craftable rods.
Fisch String FAQs
The String looks like a white albino log with a skinny shape. If you are new, you may easily be confused and mistake it for wood.
The Desolate Pocket is a sub-location of Desolate Deep and contains all the fish available to catch as part of the Desolate Deep Bestiary. However, the Brine Pool, which is also part of the Desolate Deep, has a separate Bestiary.
No, the String is effortless to catch as a trash-tier item, especially with a Flimsy or Training rod.
For more on Fisch, check All 20 Balloon Animal Locations in Fisch - Silly Fun Happy Rod or All Turkey Locations in Fischgiving 2 Bestiary (2025) - Fisch