Isles of Abyss changes the survival formula of Once Human by moving your base from solid land to the open ocean. You are no longer tethered to a static territory, as your ship now functions as your mobile home, workshop, and weapon platform. This scenario arrived as a major update on October 21, 2026, and it demands a shift in how you prioritize resources and exploration. Whether you are prepping for your first voyage or gearing up for the Sunken Lord, here is what you need to know.
How does the Isles of Abyss progression work?
Unlike standard scenarios, you start at the maximum level in Isles of Abyss. Your progression is entirely tied to Tech trees rather than character leveling. You unlock better gear and ship components by exploring the archipelago and completing objectives.
Your existing Blueprints and Mods carry over, but your current Tech level limits the rarity of items you can craft. You earn the rare Heart of the Ocean currency by completing challenges, which you then spend to unlock new Mods like Precision Load and Turret Enhancement.
Why is modular shipbuilding vital?
Your ship is not just a vehicle, it is your mobile base. You can build it using dedicated parts like hulls, gunwales, and decks in Build Mode. You should save your favorite designs as a Design Layout early on so you can quickly re-summon your ship if it takes damage or sinks.
Propulsion tiers
- Manual power: Use this for your initial coast-hugging trips.
- Sail power: Ideal for long-distance travel without fuel costs.
- Fuel power: Leverages Black Tide Fuel to increase your speed cap.
- Electric drive: The endgame option for high-performance vessels.
If you are looking for the best strategies to optimize your base and progression, our Once Human base building guide covers the fundamentals of mobile territory management.
How to survive Haywire Zones
Each region in the archipelago features a unique Haywire Zone that pressures your survival stats. Packing the right kit is essential for long-term exploration.
| Haywire Zone | Region | Key Threat | Survival Item |
|---|---|---|---|
| Mist of Deceit | Reefshadow Bay | Temperature/Visibility | Blaze Core Lantern |
| Black Tide | Misty Marsh | Stardust Contamination | Black Tide Protective Mask |
| Time Rain | Spring Valley | Energy/Hydration Drain | Time-Reverse Raincoat |
| Skyfire | Falling Ember | Meteor Damage/Heat | Cooling Patch |
If you are new to the game or need a refresher on the basics of survival, check out our Once Human beginner's guide to get up to speed on mechanics that apply across all scenarios.
Naval combat and boss encounters
Naval combat is central to the Isles of Abyss experience. You can cycle through different cannons, such as the Harpoon Cannon for marine creatures or the Frost Cannon to slow down fleeing Voyagers. For the best performance in combat, consult our Once Human builds guide to align your character stats with your naval weaponry.
Endgame boss: The Sunken Lord
Access to the Sunken Lord opens once your server reaches 100% purification. This fight takes place in a multi-level arena where you must manage tentacle sieges and spreading lava. It is a group-focused encounter that requires coordinated ship maneuvering and effective use of artillery.
Customizing your warship layout
Swapping naval weapons
Fighting the calamity tower
Pro Tips
- Auto Cruise: Use the map to mark your destination and enable Auto Cruise to manage your inventory while you sail.
- Boarding Voyagers: Don't just sink enemy ships. Damage their facilities, board the deck, and loot the hold for extra supplies.
- Diving Safety: Always keep an Inflatable Float in your inventory to quickly reach the surface if your oxygen runs low.
For a complete overview of all available resources and strategies, explore our full Once Human guides collection to master every aspect of the game.
