The Tidefall update for Fisch adds three Essences — Requis, Tide, and Thalass — that are required at the Infusion Altar in the Sunken Reliquary to progress the Mermaid content and unlock fishing rod upgrades. All three Essences are locked to Tidefall’s underground cave system and cannot be obtained anywhere else.
Where Essences Fit Into Tidefall and the Infusion Altar
Tidefall is an underwater cave network accessed through the Underwater Opening in the Ocean at GPS coordinates 3223, 130, 850. From the central Tidefall hub, four main branches fan out: Tidefall Castle, Collapsed Ruins, Coral Bastion, and Sunken Reliquary.
The Sunken Reliquary branch is where Essences ultimately come together. At the end of its long hall sits the Infusion Altar. Placing all three Essences — Requis Essence, Thalass Essence, and Tide Essence — on the altar’s pedestals summons Mella and unlocks Fishing Rod Upgrade functionality. After a single upgrade, the three Essences are consumed, unless the upgrade uses a Divine Secret fish, in which case the Essences are preserved.
Practically, this means you need at least one full set of all three Essences to access upgrades, and more sets if you plan to upgrade multiple times without relying on a Divine Secret.

How to get Requis Essence in Fisch
Requis Essence is the only Essence that does not drop from environmental objects. It is tied to a specific NPC questline in Tidefall.
Step 1: Travel into Tidefall and navigate to the Sunken Reliquary branch from the central Tidefall hub. This area is a long corridor lined with pillars and bookshelves, ending in a fishing pool and the Infusion Altar.

Step 2: Find the Magical Diver NPC inside the Sunken Reliquary. He offers a series of quests. Complete his first quest to move the chain forward if you have not already done so.
Step 3: Accept and complete the second Magical Diver quest. For this quest, you must hand over two specific creatures: a Fallen Flying Gurnurd and an Omnithal. Once you deliver both, the quest completes.
Step 4: After turning in the Fallen Flying Gurnurd and Omnithal, Requis Essence is granted directly to your inventory as a quest reward. You can then take it to the Infusion Altar when you are ready to use it for upgrades.

At this point, Requis Essence is the only Essence you own that does not require you to interact with Tidefall’s Dripstone Collapse event system.
How Dripstone Collapse Works in Tidefall
The other two Essences, Tide Essence and Thalass Essence, are tied to a timed environmental event called Dripstone Collapse. Tidefall is the only location in Fisch where Dripstone Collapse can occur.
During a Dripstone Collapse, special mineral formations called Dripstones spawn at designated points in Tidefall’s cave system. These formations can be mined with a pickaxe, and they have a chance to drop Tide or Thalass Essence, or simply yield regular rock.
There are two ways to get a Dripstone Collapse running: by relying on natural event spawns via sundialing, or by forcing an event using the Dripstone Collapse Totem.

How to get Tide and Thalass Essence from Dripstones
Step 1: Make sure you have a pickaxe in your inventory. Tide and Thalass Essence only drop when you mine Dripstones with a pickaxe; other tools will not work.
Step 2: Trigger a Dripstone Collapse. You can let one occur randomly by sundialing time forward until the event starts, or you can use a Dripstone Collapse Totem to manually start a collapse as soon as you are ready.
Step 3: Watch for the on-screen event announcement indicating a Dripstone Collapse has begun. The game surfaces this notification so you know the event is active.
Step 4: Head to the indicated spawn area for the event. Look for the distinctive Dripstone formations that appear on the terrain. These stones only exist while the collapse is active.
Step 5: Equip your pickaxe and mine each Dripstone you find. Each mined stone has a chance to drop either Tide Essence or Thalass Essence. Sometimes you will receive only rock, so expect to repeat this process across multiple stones and multiple collapses.
Step 6: Continue participating in Dripstone Collapse events until you obtain at least one Tide Essence and one Thalass Essence. Once you have both, you can pair them with Requis Essence at the Infusion Altar.

Because of the random nature of the drops and the chance of getting rock, Tide and Thalass Essences are effectively farmed by repeatedly starting or waiting for Dripstone Collapse and clearing as many Dripstones as possible each time.
How to use the Dripstone Collapse Totem to farm Essences
The Dripstone Collapse Totem is a high-cost utility item that lets you force a Dripstone Collapse without waiting for natural event rotation. It is sold in the central Tidefall hub.
Inside Tidefall, various NPC vendors sell items tailored to the area. One of these vendors offers the Dripstone Collapse Totem for 35,000,000 C$. The totem is positioned near the Fallen Rod, another high-tier purchase in Tidefall.
Step 1: Travel to the central Tidefall area from the Underwater Opening entrance. Locate the local vendors clustered around the main hub.
Step 2: Purchase the Dripstone Collapse Totem for 35,000,000 C$ once you have enough currency. This is a long-term investment aimed at players who plan to farm multiple sets of Tide and Thalass Essences or otherwise want reliable access to Dripstone Collapses.
Step 3: Use the totem in Tidefall when you are ready to farm. Activating it starts a Dripstone Collapse immediately, triggering the usual on-screen announcement and spawning Dripstones you can mine.
Step 4: During each forced event, sweep the spawn area thoroughly and mine every Dripstone with your pickaxe. Because each stone has independent drop chances, more stones per event translate directly into more opportunities to get Tide and Thalass Essences.
Using the totem removes the waiting component of Essence farming and converts it into a pure currency-for-time trade: you spend C$ upfront to compress all your Essence farming into sessions you control.

Where Essences appear and what you need to farm them
| Essence | Location | How it is obtained | Required items or actions |
|---|---|---|---|
| Requis Essence | Sunken Reliquary (Tidefall) | Reward for completing the second Magical Diver quest | Deliver Fallen Flying Gurnurd and Omnithal to Magical Diver |
| Tide Essence | Tidefall (during Dripstone Collapse) | Chance drop from mining Dripstones | Pickaxe, active Dripstone Collapse (natural or totem-triggered) |
| Thalass Essence | Tidefall (during Dripstone Collapse) | Chance drop from mining Dripstones | Pickaxe, active Dripstone Collapse (natural or totem-triggered) |
All three Essences are confined to the Tidefall cave system. None of them are obtainable in the Ocean or other first-sea locations. Requis is quest-gated; Tide and Thalass are event-gated.
Using Requis, Tide, and Thalass Essences at the Infusion Altar
Once you have collected the full trio — Requis Essence from the Magical Diver and both Tide and Thalass Essences from Dripstones — you can complete their intended use at the Infusion Altar in the Sunken Reliquary.
Step 1: Return to the Sunken Reliquary via the Tidefall hub. Move down the main hallway to the altar chamber at the far end.
Step 2: Interact with the Infusion Altar and place Requis Essence, Tide Essence, and Thalass Essence on the three pedestals. This configuration allows the altar to call Mella.
Step 3: Once the Essences are placed, use the altar’s Fishing Rod Upgrade function. This unlocks Mella’s interaction and lets you push your rod beyond standard upgrade routes.
Step 4: Be aware that after one upgrade, the Essences are consumed, unless you use a Divine Secret fish during that upgrade. With a Divine Secret, the upgrade goes through, but your three Essences remain, which is useful if you intend to experiment with multiple rod configurations.
Given the cost of the Dripstone Collapse Totem and the time required to secure Omnithal and Fallen Flying Gurnurd for the Magical Diver, planning when to spend or preserve your Essences is central to efficient progression through Tidefall’s late-game systems.

Once Requis, Tide, and Thalass Essences are understood as extensions of Tidefall’s structure — a quest chain in the Sunken Reliquary, a location-locked environmental event, and a high-cost totem to bypass waiting — the path to assembling a full set becomes straightforward. Clear the Magical Diver’s second quest, grind Dripstone Collapses with a pickaxe, and then feed all three Essences into the Infusion Altar to open up Mella and rod upgrades at your own pace.