Run the last post office on the seabed. Weigh every parcel, price it to the exact stamp, catch the forgeries, and pack the day's mail into a fish-shaped cargo hold that has to hang level. Four weeks. Four rent days. One desk between you and eviction.

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Planned Release Date: November 2026

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About This Game

Undersea Post Office is a cozy desk game about running the post office at the bottom of the sea.

Divers swim up to your porthole with parcels. Check where each one is going, pay the postage in stamps, turn away the fakes and pack everything into the cargo fish before the shift ends. Then count the money, because rent is coming.

Every shift starts with The Waterline Herald. The front page tells you what is different today: a storm that doubles the risk, a route fee that went up, a stamp shipment that came in short, forgers copying the names of real towns. Read it before you open the window.

Each day the office runs one route: Teal, Azure, Violet or Rose. When a diver hands you a parcel, find its town on the route map. If the town is not on today's route, send the parcel back. If the town is not on the map at all, someone is trying to smuggle it through.

Put the parcel on the scale to see its weight band, then look up the route price in the handbook. Postage is paid in stamps, and each colour has its own value, from the green $2 to the blue $40. They have to add up exactly. Paying too little or too much costs you $25.

Accepted parcels go into the hold, and the hold is a fish. The parcels come in odd shapes, and each day brings a fish with a different body to fill. From day 3 the fish hangs from a beam, so spread the weight and keep it level for a bonus.

At the end of the shift the ledger adds it all up: pay for every cell you filled, $10 for each forgery you caught, a bonus when every accepted parcel made it into the hold, another for keeping it level, and every fine you picked up. Rent is due on day 7. Whatever is left can go to the supply catalogue, on things like a stamp organizer or a thermos that cuts your daily costs.

FEATURES

  • A new fish-shaped hold every day, and parcels in all kinds of shapes

  • Colour-coded stamps, each with its own value

  • Four routes through real seas and straits, from the Sargasso to the Bosphorus

  • Forged parcels addressed to towns that do not exist

  • A morning paper that changes the rules of the day

  • A supply catalogue with upgrades for your desk

  • Playable in 12 languages

System Requirements

    Minimum:
    • OS *: Windows 8
    • Processor: Dual Core CPU
    • Memory: 2 GB RAM
    • Graphics: 1 GB
    • Storage: 800 MB available space
    Recommended:
    • OS: Windows 10
    • Processor: Dual Core CPU
    • Graphics: 4 GB
    • Storage: 1000 MB available space
* Starting January 1st, 2024, the Steam Client will only support Windows 10 and later versions.
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