- What to know
- Abyss Angler Cave unlock process
- Location of the Lost Captain and how his questline works
- How to unlock Angler Cave after obtaining the Pirate Key
- What makes the Ruined Gun valuable in combat
- How the Tube improves movement and exploration
- Purchase details inside Angler Cave
- Why completing the Lost Captain quests is mandatory
- Unlocking Angler Cave and its rewards
What to know
- Angler Cave is locked behind the Lost Captain’s full questline.
- Completing the final quest rewards you with the Pirate Key, required for entry.
- Inside the cave, you can purchase the Ruined Gun and Tube mobility item.
- The Ruined Gun offers high burst damage, while the Tube significantly boosts movement speed.
If you have been exploring the dark waters of Abyss and wondering how players are getting their hands on the Ruined Gun and Tube, the answer lies inside a hidden location called Angler Cave. You cannot simply stumble into it. Access is locked behind a full NPC questline, and you must complete every requirement before the cave becomes available.
The entire process revolves around the Lost Captain, an NPC who acts as the gateway to this hidden content. Once you finish all his missions, you receive the Pirate Key, which unlocks Angler Cave and gives you access to some of the strongest early-to-mid progression equipment in the game.
Abyss Angler Cave unlock process
| Requirement | Details | Why It Matters |
|---|---|---|
| NPC Required | Lost Captain | Unlocks the entire quest chain |
| Key Item | Pirate Key | Opens Angler Cave entrance |
| Location Unlocked | Angler Cave | Hidden equipment shop |
| Main Rewards | Ruined Gun, Tube | Damage boost and mobility upgrade |
| Entry Condition | Complete all Captain quests | No shortcuts available |
Location of the Lost Captain and how his questline works
The Lost Captain is located in one of the early accessible ocean-side or dock regions of the map. When you open your map, you can identify his location marked near coastal structures. You must physically travel to him and initiate dialogue to begin the quest chain. This is not a single-task mission. The Captain assigns multiple objectives that typically involve exploration, defeating enemies, retrieving specific items, or clearing hostile zones.

Each quest must be completed sequentially. If you attempt to access Angler Cave before finishing every mission, the entrance will remain locked. The final mission in the chain rewards you with the Pirate Key, which is the only method of unlocking the cave.
Because this questline serves as a progression checkpoint, the game effectively ensures you are strong enough before granting access to the Ruined Gun and Tube.

How to unlock Angler Cave after obtaining the Pirate Key
Once you receive the Pirate Key, you can travel to the Angler Cave entrance. The cave is located along the rocky coastline in a dimly lit section of the map. The entrance appears sealed until you interact with it while holding the Pirate Key in your inventory.
Step 1
Travel to the coastal area where the cave entrance is located. The entrance is embedded into rock terrain and appears locked.

Step 2
Ensure the Pirate Key is in your inventory. If it is stored elsewhere, the interaction prompt may not trigger.

Step 3
Interact with the locked entrance. The game will automatically consume or register the key and unlock the Angler Cave.

Step 4
Enter the cave and proceed deeper inside. You will eventually reach the internal vendor area where the Ruined Gun and Tube are available for purchase.

There are no additional puzzle mechanics once you have the key. The unlock is straightforward, but only available after full quest completion.
What makes the Ruined Gun valuable in combat
The Ruined Gun is a ranged weapon that delivers strong burst damage, making it highly effective against mid-tier enemies and certain bosses. Compared to starter weapons, it provides noticeably improved output per shot, allowing you to eliminate threats faster and maintain safer distance during encounters.

Its main strengths include high damage scaling and reliable projectile behavior. Players often use it to speed up farming runs or handle tougher underwater enemies where melee builds struggle. Because it is locked behind Angler Cave access, it functions as a reward for completing structured progression rather than random exploration.
How the Tube improves movement and exploration
The Ruined Tube is not a weapon but a mobility-enhancing item. When equipped or used, it significantly increases your movement speed, particularly useful when traversing open ocean zones or escaping enemy clusters.
Movement speed is critical in Abyss, especially when navigating large underwater environments. Faster traversal means quicker quest completion, improved farming efficiency, and safer disengagement from dangerous enemies. The Tube therefore complements the Ruined Gun perfectly by combining offensive power with enhanced mobility.

Purchase details inside Angler Cave
| Item | Type | Primary Benefit | Usage Role |
|---|---|---|---|
| Ruined Gun | Ranged Weapon | High burst damage | Combat efficiency |
| Tube | Mobility Item | Increased speed | Exploration and escape |
Both items must be purchased once you enter Angler Cave. They are not automatically granted upon unlocking the cave. Make sure you have sufficient in-game currency before entering so you can acquire them immediately.
Why completing the Lost Captain quests is mandatory
The developers designed this progression intentionally. The Lost Captain’s questline serves as a skill check and preparation phase. By completing his missions, you gain experience, currency, and combat familiarity, ensuring you are ready for the equipment unlocked inside Angler Cave.

Skipping this step is not possible. There are no alternative keys, shortcuts, or glitches that legitimately bypass the Pirate Key requirement. If you want access to the Ruined Gun and Tube, you must complete the full quest chain.
Unlocking Angler Cave and its rewards
Unlocking Angler Cave in Abyss requires patience and full completion of the Lost Captain’s quests, but the reward is absolutely worth it. The Ruined Gun provides strong ranged damage, and the Tube dramatically improves movement speed, making both items powerful upgrades for progression and farming.
If you are aiming to strengthen your build and move more efficiently across the map, focus on finishing the Captain’s questline first. Once you secure the Pirate Key, Angler Cave opens the door to some of the most useful early-to-mid game gear available.