How to defeat Cthulhu Boss in Fisch

So, you’ve been splashing around in the First Sea, making some pocket change.

Naturally, you want to unlock the Second Sea in Fisch. It’s where you’ll find the best fishing rods and the rarest fish. The catch, however, is that you have to take down the Cthulhu Boss. If you can’t beat him, you’re not ready for what’s waiting on the other side. But if you can? You’re officially part of the elite club of serious Fischers.

Where to find Cthulhu Boss in Fisch

Cthulhu is a multi-phase, high-pressure encounter that demands preparation and skill. You need to hit at least level 200 to get a shot at this boss. Once you’re ready to roll, your next stop is Terrapin Island, specifically the Dreamers Crypt. If you haven’t been here before, don’t worry—it’s not too hard to find. Just plug these coordinates into your GPS (you did pick one up from Moosewood, right?): 140, 150, 2050. That’ll take you to the southern part of the First Sea.

When you arrive, head to the back of the island. You’ll find a Sea Traveler NPC standing in front of a giant greyed-out stone door. You’ll be teleported into the Cthulhu Boss chamber once you pass the Sea Traveler’s “Are you ready?” test.

How to beat Cthulhu Boss in Fisch

This is where things start getting real. The first thing you’ll notice is the Keeper’s Torch sitting on the ground. Pick it up immediately—it’s your primary weapon for this fight. Without it, you’re just a sitting duck.

The Keeper’s Torch lets you launch fireballs at Cthulhu, but that alone won’t do much damage. Quickly find the lanterns. They’re the key to actually taking Cthulhu down.

Cthulhu’s health bar is divided into six color phases—Red, Orange, Yellow, Green, Blue, and Purple. To deal maximum damage, you need to match your torch’s flame color to the current phase of the health bar. The lanterns that let you imbue your torch with the correct color are perched on small platforms around the arena. And to reach them, you’ll have to complete some quick and tricky parkour challenges.

The process looks like this:

• Check the rightmost color on Cthulhu’s health bar (this is the current phase). 
• Locate the lantern that matches that color in the arena. 
• Jump across platforms to reach the lantern. (Pro tip: don’t rush—falling will waste precious time.) 
• Press E to imbue your torch with the lantern’s flame. 
• Attack Cthulhu with the matching flame.

Repeat this process for all six colors, and you’ll chip away at Cthulhu’s health bar in no time.

While the lantern mechanic is the main focus, there are a few other things to keep in mind. This fight is technically soloable, but having a couple of friends makes it so much easier. They can help cover different lanterns, reducing the time you spend parkouring around the arena. Cthulhu’s attacks can deal heavy damage if you’re not careful. Keep moving, and use the lanterns as cover. If you have Glimmersuit boots, use them. It will make navigating the platforms much faster.

Once you’ve defeated Cthulhu, head back to the Sea Traveler NPC at the Dreamers Crypt. He’ll grant you access to the Second Sea, where even greater challenges await.