Portugues
Undertow
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About the game
A wreck has scattered its survivors across the sea, floating in life jackets, and your submarine has to get them to safety. They lie all the way from your own harbour to the raiders' port, some at the surface and some slowly sinking. Raider ships sail out empty, trawl back toward their port lifting people with a crane, and anything they carry is lost the moment they arrive.
You catch survivors just by touching them, at any depth, and carry up to eight at a time to your harbour or hand them to the ferry. A raider loaded with people is slow, so the trick is to sink it before it reaches port: everyone aboard spills into the water, and they sink fast, so you have to catch them before the seabed. Escort destroyers drop depth charges when you come close, and raider submarines hunt in the deeper water.
The whole sea is longer than the screen, so a radar strip at the top shows every ship and every survivor. There are eight waves, each more crowded than the last.
Playing it here
Click Play, then press a key or tap inside the game to start. The high-score table is kept in your browser only and nothing is sent anywhere.
Controls
| Input | Action |
|---|---|
| Arrows / WASD | move the submarine |
| Z, X, Space, J | fire a torpedo |
| M | mute |
A few things worth knowing
Watch the radar. The strip at the top shows where the raiders are headed; sink the loaded ones first.
Dodge the depth charges. A destroyer drops three in a row at your depth: attack from ahead of the raider, or from deep enough to be out of range.
Mind the hold. It takes eight. Drop them at the harbour before going back for more.
Questions
How do I save a survivor? Carry them to your harbour. They are only safe there, and only lost at the raiders' port.
Is there a limit on time? Each wave ends when everyone is saved or lost.
Credits and licence
Undertow was made by Kenta Cho (ABA Games) with Claude Code, using the agentic-gamedev-skills, and published under the MIT licence in the agentic-gamedev-games repository. The licence text is linked from this page. The game files are served as published, with only the starting page replaced so that nothing is loaded from other sites.