FISCH Luminescent Cavern Guide: How to Find Keystones, Unlock Secrets, and Boom Ball

Your ultimate guide to the FISCH Roblox Luminescent Cavern update. Learn how to get to the new area, find all the Keystones, unlock the Crimson Cavern, and discover the secret rewards.

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The waters of FISCH have just gotten a whole lot deeper with the massive new Luminescent Cavern update. This latest content drop introduces a sprawling, secret-filled cave system for players to explore, complete with new quests, powerful gear, and rare fish to catch. Getting there, however, involves a multi-step puzzle that requires you to hunt down mysterious Keystones.

This comprehensive guide will walk you through everything you need to know, from the first step of your journey into the Desolate Deep to the final rewards waiting in the darkest corners of the brand-new Crimson Cavern.

Finding the Path: How to Access the Luminescent Cavern

Your adventure begins in a familiar location, but a new path has opened for those observant enough to find it. The entrance to the Luminescent Cavern is hidden and sealed, requiring you to solve a puzzle before you can gain entry.

Step 1: Set Sail for the Desolate Deep

First, you’ll need to spawn your boat and make your way over to the Desolate Deep biome. This gloomy, deep-water region is the starting point for unlocking the new content.

Step 2: Locate the New Cavern Entrance

Once you arrive in the Desolate Deep, you need to look for a new pathway that wasn’t there before the update. Follow the main channel, but keep your eyes peeled for a new opening that veers off to the right. Navigate your boat through this passage. As you proceed, you will eventually come across a large, sealed wall with a

mysterious crack in it. This is the entrance you’re looking for.

Step 3: The Keystone Pedestal Puzzle

In front of the cracked wall, you will find a pedestal. Interacting with it reveals that you need to place a “Keystone” to proceed. This isn’t just one item, but a series of them. The update has scattered several unique Keystones across the world of FISCH, and you’ll need to find them to unseal the path. This is the main puzzle of the update.

The Great Keystone Hunt: All Locations Revealed

The key to entering the Luminescent Cavern is finding the corresponding Keystones hidden throughout the world. Each Keystone is tied to a specific island or biome, and you must find it and bring it back to the pedestal.

### The Fossil Keystone

The first keystone you’ll likely be tasked with finding is the

Fossil Keystone. As the name implies, this ancient artifact is connected to the game’s prehistoric region.

• Location: The Fossil Keystone spawns randomly in the waters surrounding the Ancient Isles.
• How to Find: Circle the island slowly and keep an eye out for a distinct, fossil-like object resting on the seabed near the shore. It has a unique shape, making it stand out from the regular rocks and scenery.

### The Sunstone Keystone

The next piece of the puzzle is the Sunstone Keystone. This item glows with a warm, orange light, hinting at its fiery origins.

• Location: This keystone is found on Sunstone Island.
• How to Find: Unlike the Fossil Keystone, this one isn’t underwater. You’ll need to dock your boat and explore the island itself. The Sunstone Keystone typically spawns near the peak of the island’s volcano, often tucked behind a rock formation.

### The Coral Keystone

This keystone is beautifully encrusted with vibrant marine life, making it both stunning and difficult to spot.

• Location: This item is hidden within the Coral Reef biome.
• How to Find: The Coral Keystone is found deep within the reef’s intricate structures. You will need to carefully navigate through the colorful coral formations. Look for an unusual glint, as the keystone is often camouflaged among similarly colored corals.

Once you have collected and placed all the required Keystones on the pedestal, the mysterious crack will shatter, opening the path forward into the mysterious river and, ultimately, the Luminescent Cavern.

Exploring the Depths: The Luminescent and Crimson Caverns

Once inside, you’ll discover a breathtaking new environment teeming with secrets and rewards.

The Luminescent Cavern

True to its name, this cavern is a sight to behold. It’s illuminated by glowing flora, bioluminescent fungi, and schools of shimmering fish you can’t find anywhere else. This area is a fishing paradise, offering a completely new roster of rare and exotic catches that are worth a significant amount of money.

The Crimson Cavern

The exploration doesn’t stop there. Deeper within the Luminescent Cavern lies a second, even more mysterious area: the

Crimson Cavern. The entrance to this cavern is sealed by another puzzle, one that requires you to “discover its power”. To do this, you must catch the new “Luminescent Guardian” fish from the first cavern and present it at the crimson-hued rock wall.

Inside, the environment shifts to a menacing red glow. This area is home to the game’s first-ever hostile fish, which will attack your line, making every catch a challenge. However, the rewards are worth the risk, as the rarest fish in the game now reside here.

New Quests, Gear, and Secrets

The update is packed with more than just new fishing spots. There are new objectives to complete and powerful items to earn.

• The King’s Crown: A new quest tasks players with finding the lost King’s Crown and returning it for a special reward. The crown can be found at the very end of the Crimson Cavern, guarded by a powerful legendary fish. Returning it to the King NPC at the main port will grant you the “Royal Scepter,” a unique fishing rod with unparalleled stats.
• The Boom Ball: This new piece of gear has a “secret method of obtainment”. To get it, you must craft it using a new, hidden recipe. You’ll need one of every rare fish from both the Luminescent and Crimson Caverns. Once crafted, the Boom Ball acts as a special lure that can be used once per day to guarantee a legendary fish spawn at your location.
• New High-Tier Rods: The update also introduces a new set of S-tier fishing rods, referred to as the “Rods of Unlimited Power”. These can be purchased from a new vendor inside the Luminescent Cavern, but they require you to trade in specific, ultra-rare fish from the Crimson Cavern.

This update adds a fantastic layer of exploration and puzzle-solving to the game. For players who enjoy diving into new content and uncovering secrets, it’s a must-play. And if you’re looking for more ways to get ahead in your favorite games, be sure to check out our list of active Roblox codes for September for other titles.

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