A tide-locked world has one face in permanent day and one in permanent night. Between them runs a narrow band where the air is survivable — a ring you could walk around, if you had the years. Everything that matters on The Sill of Hab happens inside that band.
Which means the only industry worth having is the manufacture of breathable weather. And once you can manufacture weather, you can withhold it.
They can sell the sky by the hour.
Worlds are made of consequences, not maps
Most worldbuilding stops at the map. You get the geography, the pantheon, the names of six kingdoms, and none of it presses on a character standing in a room. A world is not a setting — it is a set of pressures that make certain choices expensive.
So the sections here are written the other way round. Not “here is the climate” but “here is what the climate makes impossible.” Not a list of factions, but who owes whom air, and what happens on the day the debt is called.
What is deliberately missing
Every world in the catalogue includes a section on absences: the things this place does not have, and what grew in the space they left. On Hab there is no word for horizon that does not also mean edge of the breathable. There is no burial. There is no season.
Those gaps do more work than any map. They are where a story finds its friction.
What you get
Twenty-four sections, from geography to canon. Consequences, absences and continuity rules. A typeset PDF, and the same material as unbranded Markdown — the editable source, so you can rename anything and fold it into a book of your own.
Written once, sold once. When it goes, it leaves the catalogue for good.
