Once Human: Isles of Abyss Sets Sail October 21 – Ships, Diving and a 21-Day Ocean Scenario

Once Human Isles of Abyss launches after maintenance on October 21, 2026 (Pacific time). It's a free, PvE ocean scenario that takes Once Human's survival to sea: you'll build and sail your own ships, dive for sunken treasure, fight enemy vessels with cannons and survive strange weather on a chain of islands. Starry Studio's dev blog laid out the full details on October 16. Here's everything confirmed.

Once Human: Isles of Abyss at a glance

When does Once Human Isles of Abyss release?

Isles of Abyss goes live after the maintenance update on October 21, 2026, Pacific time, which for Europe means October 21 or early October 22 depending on when maintenance ends. Starry Studio hasn't given an exact unlock hour. Once you've created a character and finished the new player experience, you sign up from the scenario selection screen, the same way as other scenarios. Players already in another scenario can sign up from the scenario sign-up screen.

Is Isles of Abyss free?

Yes. Starry Studio's announcement art describes it as a free ocean DLC, and Once Human itself is free to play.

How do the phases and servers work?

The core cycle lasts about 21 days:

• Phase I: roughly 5–10 days. It gets shorter the faster the server pushes its purification progress.
• Phase II: 11 days. As purification advances, the endgame challenge against the Sunken Lord unlocks.
• Rest stage: after both phases end.

Each server has 12 worlds. At launch there's no Vision Tag; an Isles of Abyss Vision World opens later alongside the Season 5 Vision. A permanent server is expected on November 12, 2026 (PT), before the first servers close, so everyone can merge into it.

What is the story of Isles of Abyss?

A shipwreck strands you in the archipelago. Malla, an experienced captain who can sense the pasts of the drowned through "communion with the deep", rescues you, while the blunt Ran helps you investigate. Ships' journals, artifacts and deep-sea memories gradually reveal the link between the wandering Voyager, the looming Calamity Tower and the Sunken Lord, who draws power from trapped memories.

What are the islands and Haywire Zones?

The archipelago runs from tropical coconut groves to cold tundra. Each region has its own Haywire Zone weather that changes the survival rules and produces special resources:

• Fragrant Cape: the starting area, with flower fields, coconut groves, city ruins and grounded shipwrecks.
• Reefshadow Bay – Mist of Deceit: cold tundra and floating ice. The mist lowers the temperature and your view shrinks as your HP drops. Gathering Mist Core Grass gives Wicks for cannonballs and electricity.
• Misty Marsh – Black Tide: giant trees and toxic marsh. The Black Tide spreads Stardust contamination and drains Sanity, but yields Black Tide Clots for diving items and water facilities.
• Spring Valley – Time Rain: mangroves, waterfalls and giant crocodiles. Time Rain drains Energy, Hydration and gear durability, but speeds up crops and animals.
• Falling Ember – Skyfire: an active volcano. Meteors strike, heat the area and spawn Deviant guards; mining them gives Skyfire Gold for alloy ship parts and automated gathering.

How does ship building work?

Ships are your vehicle and a movable water territory. You build them freely in Build Mode from hulls, gunwales, bows, decks, handrails and bulwarks, in wood, iron, steel or alloy, and you can save designs to rebuild them quickly. Propulsion goes from manual and sail power up to fuel and electric drive, with Boosters and side thrusters for agility. You can mark a route and switch on Auto Cruise, and underwater teleport, cross-world return to ship and on-board respawn are all supported.

What ship cannons are there?

Cannons unlock as you advance your Tech: the Harpoon Cannon (good against sea creatures), Long Cannon, Rapid-fire Cannon (handy for the Calamity Tower's weak spots), Repeating Long Cannon, Shotgun Turret, Frost Cannon and Corrosion Cannon. Phase II adds the Rocket Launcher, Oil Drum Launcher, Repeating Shotgun Turret and Freezing Cannon. You can also ram or lay traps with a Naval Mine Launcher, and switch weapons on the wheel mid-battle. Enemy Voyagers roam the seas: destroy their key facilities, board them and loot their holds.

What can you do underwater?

Diving is a big part of Isles of Abyss. The Basic Diving Suit resists ocean contamination, and the Shark Diving Suit adds more protection and swim speed. An Oxygen Tank kicks in when you run out of air, an Inflatable Float gets you up fast, and the Spear Gun handles underwater enemies. Follow treasure maps from beachcombing, fishing and quests to shipwrecks, sunken buildings, coral ore and leaking underwater laboratories. New sea life includes the shark, tuna, jellyfish, an Anglerfish whose lure protects you from contamination and a Bubble Fish that refills your oxygen.

What else is new?

• Bay Crocodile: capture one with a Tranquilizer Throwing Needle, breed it and ride it on the water for damage reduction.
• Fishing and farming at sea: trawl nets on your ship, Tidal Cages to breed fish, and an Abyssal Sea Fishing Rod for sharks and tuna.
• Offshore production: Drilling Wells for abyssal sea oil and Black Tide Fuel for generators and propellers.
• Beachcombing: search sand holes and reefs, and open drift bottles for treasure maps, blueprints and letters.
• New seafood dishes and drinks, from Stealth Cuttlefish Sashimi to the Old Captain's Spirit.

Watch the Isles of Abyss trailer

The official release date reveal trailer, published on Xbox's channel.

More Once Human and survival on iGame Magazine

• Once Human game hub – all our Once Human coverage
• How to change your appearance in Once Human
• How to get Rain Man in Once Human
• Windrose guide – another survival game built around ships and the sea

Once Human: Isles of Abyss FAQ