April 2025: a ship, an inventory, and some fish
Devlog #1 went up on 23 April 2025. In it I said I had been building I Thalassa solo for a few months, inspired by No Man's Sky. What actually existed was a ship that moved, an inventory that held things, some fish running a wander script, and enemy AI that worked as long as you did not look at it too closely.
Twenty-nine devlogs later that same ocean has physics, an economy, a story with an ending, and other players in it. One devlog roughly every sixteen days, for fifteen months, alone. This is the road.
The ocean learned to push back
The first real turn was physics. Ships stopped sliding around like objects and started answering to forces, inertia and the terrain they hit. The world learned to loop, so sailing past the edge brings you back on the other side like a small planet. A build system arrived, then modular construction with walls, weapons and a delete mode. The submarine went in. Creatures got a proper state machine instead of scripted paths, and enemy ships got spawner waves and health bars.
It stopped being empty
Then came the parts that make a world feel inhabited. Traders with a real economy behind them: prices that decay, stock that comes back, a price history for every item. Missions hooked into combat, building and exploration. Localization, first to five languages and then eight, with Japanese, Russian and Chinese. Save slots that remember your fleet, your fuel and your hull. Bodyguards you recruit by swimming up and boarding. Sea animals you can ride, with the camera banking into the turns.
It started to hurt
Survival landed late and changed everything. Oxygen drains faster the deeper you go, and running out is not a number reaching zero, it is the whole screen closing in on you. Refinery modules turn salvage into air and power, so every dive became a round trip you have to plan. Sea currents you catch with a boost. And a playable duck with a holographic dialogue system, carrying fragments of Dr. Shinoise back to Thalassa's lab.
It went online
The last devlog before the playtest was the biggest one yet. Ship against ship over the network, boarding, with your bodyguards and mounted sea animals in the fight. A battle royale mode. Steam invites. And the Shinoise story finished, seven chapters in eight languages, with a Lore Codex holding every fragment you ever recovered.
What twenty-nine of these actually taught me
The first thing is that a devlog every two weeks is a design tool, not a marketing one. Knowing that something has to be shown on camera in fourteen days kills the features that only make sense in a spreadsheet. If I cannot film it, it usually was not worth building.
The second is that I still do not know which parts of this actually work. I have watched myself play this ocean for fifteen months, which makes me the worst possible judge of it. Twenty-nine devlogs tell you what got built. They tell you nothing about whether any of it is good. That is the one question I cannot answer on my own.
It is playable right now
The build from devlog #29 is open. Access runs through the Discord server: join, pass #verify and #rules, then pick up your key in #playtest-code.
Join the playtest: discord.gg/AYh7DrKDqg
Every devlog, with its video, is on the site: sanliuk.com/ithalassa
Devlog #30 lands here as well as on YouTube. A wishlist saves the game for later. Following is what puts it in your feed.
Manuel Hosseini