jcoffey-dev 6c388f5bc4 Convoy intent, coasts in support, and what a disrupted convoy is
122 of 139 movement cases now.

Intent, which decides whether two units swapping bounce or sail past each
other: an army goes by convoy if it was ordered to, or if its own power gave
a legal convoy order for that move. Somebody else's fleets offering a route
is not intent however good the route, and your own fleet offering from a sea
it could never do it from is not intent either, because that was not an
order. Once intent exists any ordered route may carry it, foreign or not.

A convoy order is only an order if water could actually carry that army past
that fleet, which is a question about the map and is now asked.

Support is given to a province, not to a coast of one: a fleet in Marseilles
may support an attack on the north coast of Spain although it could never
sail there. And a support is only as legal as the move underneath it.

Two bugs of my own. Convoy routing could not start from or arrive at a
province with two coasts, because the fleet graph has no bare entry for one
-- there is no 'bul', only 'bul/ec' and 'bul/sc' -- so an army boarding in
Bulgaria found no sea and stayed home. And I had read 'disrupted' as the
escort being sunk when it means the army not arriving; in Pandin's Paradox
the fleet survives and the army still does not get there.
2026-09-09 06:19:45 -07:00
2026-09-09 00:20:54 -07:00

Great Powers

A browser rebuild of the classic seven-power negotiation game: one human against six computer powers, in one sitting.

Not the name you expect, and NOTICE.md will make the argument at length once there is more to notice. The short version is the one the starship game already made on this site: the rules are free to rebuild, the trademark and the published artwork are not. "Great Powers" is what those seven were called at the time.

What this is, and what it is not

One human, six computer powers, one sitting. The original is seven people over weeks. A hub with no traffic cannot deliver that, and nobody is going to wait months for six strangers — so the other six are played by the machine and a game is finished in an evening.

It still has to be a negotiation game. A version where you simply write orders is a good movement puzzle and not this game. So:

  • Both sides open. Bots approach you with proposals; you approach them. Neither waits for the other.
  • On real terms. Offers are concrete and about this turn or the next few — support this move, keep out of that province, no attack until 1903 — and are accepted or refused on their merits, not by a die roll.
  • Betrayal is a move, not a bug. A bot can agree to support you and then not do it, and so can you. Bots remember who kept their word, tell each other, and price you accordingly. That is the game.

The press is structured rather than free text: typed offers, deterministic reasoning, and no model anywhere in it. That makes betrayal auditable — you can read exactly why a power turned on you — and testable, which free text would not be.

The look and the sound

Cartoony. Flat cel fills and one heavy outline, the same house style the other three games use, on a map generated from the topology in src/game/map.ts rather than traced from anybody's board.

It gets the whole screen. The other three games live in a four-by-three cabinet because the machines they are rebuilding did. This one is not rebuilding a machine, and seventy-five provinces plus somebody trying to talk you out of Galicia do not fit in a letterbox. The map takes the viewport.

The music is not cartoony, and that is the point. It is 1914: serious, and intense. The joke of this game is that something charming to look at is the cruellest thing on the site, and the score is what says so.

And the turn should be heard. Orders resolve in silence in every online version of this game, which is a waste of the one moment anybody cares about. Armies grinding into each other, guns at sea, a convoy escorting something across, a unit being built, a unit falling back -- each of those is a different noise, generated by the synth like everything else on this site.

The endings get their own. This game does not end in a win or a loss, it ends in one of four things, and they do not sound alike:

  • the solo -- eighteen centres, and the only unambiguous victory there is;
  • elimination -- your last centre gone, which can happen in 1903 and leaves you watching;
  • the draw -- nobody reaches eighteen and the survivors agree to stop. This is what actually happens most of the time, and it is neither a win nor a loss, so it cannot borrow either of their tunes;
  • somebody else's solo -- you are still on the board and it is over anyway, which is the bleakest of the four and should sound like it.

The board

Seventy-five provinces, two adjacency graphs — an army walks the land, a fleet follows the water — and three provinces with two coasts that do not connect, where a fleet has to say which one it is on.

The topology is a fact about a published game and free to use. The artwork is not, and there is none here: the map this game draws is generated from the data, the way the cave game's dodecahedron is.

npm test checks the board against itself. The one that earns its keep is symmetry: an adjacency list this size is typed by hand once and wrong in three places unless something looks. It found the Skagerrak wired to the Baltic on the first run — which would have quietly opened a back door into the Baltic and made Denmark worthless.

Still to build

  • the adjudicator, and the DATC cases that prove it
  • the press: offers, memory, and the arithmetic of betrayal
  • the bots' actual play
  • the map, the orders, the music
S
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Imported from github.com during the 2026-09-20 standup (local dir: great-powers)
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