The Swinging Seas / Pendulum Coast
Tumbaloo
The tide goes out. The tide comes back. With a city in it.
A massive companion planet drags Tumbaloo's oceans back and forth in colossal surges. Whole basins swap water through narrow channels, colder shores freeze, then warm floods return.
Locals live by exact tide tables. Some cities pack up and move twice a day. Some coastal creatures grow legs on a schedule.
Twice a day the companion planet swings close and the oceans pile up into a moving wall of water. It doesn't crash; it flows, roaring through stone channels, turning valleys into seas and seas into mudflats.
Everything here has adapted. Trees fold up. Houses float. Whole towns stand on mechanical legs and simply walk uphill when the water comes.
Atmosphere
Salt spray, freezing gusts, then a roar.
Local quirk
Being five minutes late here is a nautical event.
Regions · proposed names, not locked canon
Pendulum Coast
The surging channels.
Walking Cities
Settlements on stilts and treads.
The Gulp
A giant whirlpool channel where two oceans swap places. Locals ride it in barrels for fun.
Low Market
A bazaar that only exists at low tide. Shop fast.
Hazards
- ▲World-scale tidal surgesWalls of water that move faster than most ships can lift off.
- ▲Flash freezesRetreating tides leave puddles that freeze in seconds, with you in them.
Visitor tips
- ✦Set three alarms.
- ✦Park on legs, not wheels.
- ✦Read the tide table the right way up.
Local life
- ●Tide-scheduled townsfolk
- ●Shore crabs that sprint inland
A day on Tumbaloo
The day is measured by the tide horn. One blast: pack up. Two blasts: start walking. Three blasts: you should already be walking.
Between surges, the beaches are covered in strange stranded creatures and children racing to put them back.
Locals & customs
Zuggadoo gift markets
Zuggadoo traders swap ever-bigger presents along the Pendulum Coast. Never say a plain thank-you there.
Tidekeeper Mollo
Keeps the master tide-clock and has not been late for anything in forty-one years.
Sprint crabs
Shore crabs that grow legs on schedule and run inland. They are very competitive.
- ◆Punctuality is sacred. Being late is a crime and also a tide.
- ◆Every walking city has a name, a birthday and a favourite hill.
- ◆A barrel ride through the Gulp is a coming-of-age tradition.
Legends & history
The Swinging Sister
The companion planet is called the Sister. Locals say she pulls the oceans because she misses them.
Once every hundred years the Sister swings closest of all, and the Great Tide covers everything. The last one is coming soon.
Crew log
“The table was upside down. Anyone could have made that mistake.”
“Nobody else made that mistake.”
Story seed · in development
Tide Me Over
Onobo needs a tide-clock and inertial anchors. Zamfyr reads the tide table upside down. They land at exactly the wrong minute.
Someone has stolen the master tide-clock, and without it every walking city is guessing. The thief's ship is heading for Earth's orbital docks.
Earthward stakes
A stolen tide model could disrupt shipping and orbital systems back home.
Onobo packs
Science inspiration
Strong gravitational tides and orbital resonances are real. A clockwork world-scale rhythm like this is fictional extrapolation.
NASA: tides & tidal locking