Completing the Obsidian Trench Bestiary is one of the main goals in Fisch’s newest Mariana’s Veil content. The page contains 12 entries, but the final two are much more complicated than the regular trench fish.
In this guide, I’ll show you exactly what you need to catch, which conditions matter, how to trigger Skolopendra, and what you get for completing the entire page.
The general order is simple: finish the 10 regular trench species, catch the Veiled Charybdis, use it to awaken Skolopendra, and then complete the final boss encounter. Once every entry is filled, you’ll receive the Obsidian Chunk Bobber and unlock access to the Chasm-Stalker Rod.
Fisch Obsidian Trench Bestiary Guide – All Fish, Species
You can’t immediately enter the Obsidian Trench and start filling the bestiary. First, you need to complete the required Mariana’s Veil progression and open the Abyss Gate.
Start by speaking to Vaelor in Roslit Bay. He sends you to investigate the glowing mineral veins throughout Mariana’s Veil.
You’ll then need to complete the specialized mutation quests for his five descendants:
| Descendant | Layer |
|---|---|
| Ignis | Volcanic Vents |
| Glacius | Challenger’s Deep |
| Tenebris | Abyssal Zenith |
| Luminis | Calm Zone |
| Resonus | Veil of the Forsaken |
Each descendant has their own fishing requirements, so you’ll need to travel through all five layers and complete their objectives.
After finishing those quests, continue into the deeper part of the abyss and locate the Crevice Wall.
Solve the Crevice Wall Riddle
The Crevice Wall contains a riddle that points toward the different layer mutations.
You’ll need to decipher the clues and identify which fish and mutations correspond to the different sections.
Once you understand the clues, your next objective is to ignite all five layer gems.
These gems are connected to the five layers you worked through during the descendant quests. Once they’re all activated, the Abyss Gate opens.
That gives you access to the Obsidian Trench.
Deal With Trench Suppression
As soon as you enter the Obsidian Trench, you’ll be affected by Trench Suppression.
This environmental debuff reduces your effectiveness while you’re inside the trench, making longer fishing sessions increasingly difficult.
Thankfully, there is a way to temporarily remove the suppression.
Look around the trench for the glowing white crystals. Interacting with these crystals temporarily purges your suppression level.
Before settling down to complete the bestiary, I recommend locating several crystals around your preferred fishing area. That way, you won’t have to waste time searching for one when the suppression starts becoming a problem.
Obsidian Trench Bestiary Entries
The Obsidian Trench contains 12 total species.
The first ten are regular trench catches:
- Obsidian Gaveltooth
- Cinder-Crust Gar
- Scoria Scorpionfish
- Shatter-Tooth Shark
- Magma-Glass Marlin
- Tectonic Toadfish
- Ash-Cloud Angelfish
- Shatterjaw Shark
- Pumice Puffer
- Basalt Behemoth
These are the easiest entries to complete because they don’t require the special boss mechanics used by the final two entries.
Your goal should be to keep fishing until only the special silhouettes remain on the bestiary page.
Fastest Way to Complete the First Ten Fish
For the normal trench entries, the main thing you want is faster catches.
If you have the Toxinburst Rod, it’s particularly useful here because its passive can pull additional fish alongside your main catch. This can help you fill several bestiary entries much faster than fishing normally.
You can also use the harpoon when dealing with heavier targets such as the Tectonic Toadfish.
There isn’t a complicated activation mechanic for these ten fish. Just keep fishing in the Obsidian Trench until all ten standard entries are registered.
Once those are done, the real challenge begins.
How to Catch Veiled Charybdis
The Veiled Charybdis is the first of the two special entries.
Unlike the regular trench fish, Charybdis is found in the rivers inside the Obsidian Trench.
Its listed fishing requirements are:
| Fish | Bait | Weather |
|---|---|---|
| Veiled Charybdis | Meteor / Stag Beetle | Night |
You’ll want to fish for it at night while using either Meteor or Stag Beetle bait.
When you hook Veiled Charybdis, the encounter changes into a special high-stakes fishing minigame.
Watch Out for the Charybdis Whirlpools
The biggest danger during the Veiled Charybdis encounter is the whirlpools.
These can interfere with your rod control while you’re trying to reel in the fish. If you simply continue fighting the fishing bar without reacting to the whirlpool, you can quickly lose control of the encounter.
Pay attention to the water and react as soon as the whirlpool appears.
Once you successfully catch Veiled Charybdis, its entry will be added to your bestiary.
But don’t leave the trench yet.
You’ll need to catch Charybdis several more times to trigger the final encounter.
How to Awaken Skolopendra
Skolopendra does not simply appear on a normal fishing cast.
You need to trigger its awakening yourself.
Catch approximately 4 to 6 Veiled Charybdis in the Obsidian Trench.
Once you’ve reached the required number, you’ll notice that the trench starts changing.
The crystals throughout the area turn deep red, signaling that something has awakened.
That’s your indication that Skolopendra has risen.
Skolopendra Catch Requirements
Skolopendra has its own special requirements:
| Requirement | Details |
|---|---|
| Bait | Kraken Tentacle |
| Weather | Rain or Foggy |
| Season | Autumn or Winter |
| Encounter | Special boss minigame |
Make sure the required weather and season conditions are active before attempting to complete this part.
Unlike the regular fish, Skolopendra uses a dedicated boss-style fishing encounter with additional effects.
Complete the Skolopendra Encounter
Once Skolopendra has awakened, start the boss encounter and focus on maintaining control throughout the minigame.
This isn’t a normal fishing battle, so don’t treat it like one of the standard Obsidian Trench catches.
The encounter includes unusual effects that can make controlling the fish more difficult. Stay patient and concentrate on the fishing bar instead of trying to force the catch.
Successfully catching Skolopendra fills the final bestiary entry.
At that point, all 12 Obsidian Trench species should be registered.
How to Get 100% Obsidian Trench Bestiary Completion
The completion order I recommend is:
- Unlock the Obsidian Trench.
- Catch all 10 standard trench species.
- Catch Veiled Charybdis.
- Catch Veiled Charybdis until Skolopendra awakens.
- Wait for the correct Skolopendra conditions.
- Use Kraken Tentacle.
- Complete the Skolopendra boss encounter.
- Check your bestiary for 100% completion.
Once every silhouette is filled, the game will display the completion confirmation.
You should also receive the Obsidian Chunk Bobber as the completion reward.
Obsidian Trench Bestiary Catch Order
If you just want the shortest version of the progression, follow this order:
10 regular fish → Veiled Charybdis → 4–6 Charybdis catches → Skolopendra → 100% completion
The important part is not trying to hunt Skolopendra before you’ve completed the Charybdis requirement. You need the Charybdis catches to trigger its awakening first.
How to Unlock the Chasm-Stalker Rod
Completing the Obsidian Trench content and defeating Skolopendra also contributes toward unlocking the Chasm-Stalker Rod.
After conquering the trench, look for the crystal interaction in the area. The rod becomes available for purchase through the crystal prompt once the required progression has been completed.
The Chasm-Stalker Rod comes with its own unique mechanics, including a new mutation, strong passive effects, and a streak system exclusive to the rod.
So completing the Obsidian Trench isn’t just about filling another bestiary page. It’s also an important part of progressing toward one of the newest rods in Fisch.
Obsidian Trench Bestiary Rewards
Completing all 12 entries gives you the Obsidian Chunk Bobber and confirms the Obsidian Trench Bestiary at 100%.
More importantly, finishing the trench’s progression helps unlock the Chasm-Stalker Rod, which is one of the major rewards associated with the new content.
The bestiary itself is relatively small, but the final two entries turn it into a proper challenge. The ten regular fish can be handled through normal farming, while Veiled Charybdis and Skolopendra require specific conditions and special encounters.
If you’re stuck at 10/12, don’t keep fishing randomly. Start working on Veiled Charybdis, build up the required catches to awaken Skolopendra, and then finish the final boss encounter to complete the page.