Eight Stars

Quick start

Tap a City tool (A/B/C) and tap the map — the center claims the 3×3 around it.
Paint terrain to match your game: crops, forests, mountains with ore. These are what buildings feed on.
Extend territory with the Territory tools if your city's borders have grown (up to the 5×5 around its center).
Captured a city with buildings already standing? Mark them with the existing building tools.
Press Solve for the best plan, then More plans to see cheaper lower-income options.

Your map is saved in this browser automatically. Undo steps back through your edits, and Copy link gives you a URL that opens the map anywhere.

Reading the board

Terrain: plain green = field, yellow rows = crop, dark green trees = forest, grey peak = mountain, peak with a dot = ore, blue waves = ocean.
A colored border is city territory (red A, blue B, purple C); the letter marks the city center.
Dark red letters are buildings that already stand on the tile (fa farm, h hut, mi mine, S/W/FO sawmill/windmill/forge, M market, mo monument).
After solving: M +n★ is a market and its income, S/W/FO Ln a producer and its level, fa/h/mi the supporting farm/hut/mine that feeds it.
An existing building drawn grey and crossed out is one the plan demolishes (that is how a market or producer moves to a better tile, since a city only gets one of each). A small letter in a tile's corner is what used to stand there.
Tap any tile coordinate in the plan text to flash that tile on the map.

Rules the editor enforces

Placing a city center claims its 3×3; territory can only be painted within the 5×5 around a center.
Buildings must stand inside territory. Farms need crop, huts need forest, mines need ore; painting incompatible terrain under a building removes it.
Each city gets one market, sawmill, windmill and forge; placing a second one moves the first.
Before solving, the map is checked against the game's placement rules (centers 3–5 tiles apart, territory within reach, one of each special per city) and problems are listed.

The options

Clear forest (Forestry): build on a forest tile, refunds 1★.
Burn forest (Chivalry, 3★): forest becomes crop, for a farm.
Grow forest (Spiritualism, 5★): a field or crop tile becomes forest — enables field/crop → lumber hut, and the field → grow → burn → farm chain.
Destroy buildings (Chivalry): with it off, existing buildings — monuments included — are permanent fixtures the solver must work around.

Challenge mode

A random 10×10 map with 1–3 cities is dealt as soon as you open the tab. Place buildings with the Build tools and watch your income and cost update live; the erase tool removes your own building or demolishes a pre-built one (free, as in-game). About half the maps start partly built — sometimes with a slice of the best plan, sometimes with a decoy village in the wrong place.

Check my plan grades you against the solver's proven optimum: ★ for 70%+ of the best income, ★★ for the maximum income, ★★★ for the maximum income at the provably cheapest cost. Show solution reveals the optimal plan; Back to my plan returns to yours.

Understanding the results

Income is stars per turn from markets; cost is the one-time stars to build everything (terrain conversions included); the payback is how many turns until the plan has paid for itself.
Proven optimal means an exact integer-program solve found the plan and proved nothing better exists. A plan marked near-optimal hit the time limit — it is the best found, but not proven best.
More plans lists the cheapest plan for every worthwhile income level: each step down in income is strictly cheaper. Gaps (e.g. 13 then 9) mean the levels between cost the same as the higher plan.
Adjacency counts all 8 neighbours and works across city borders. A market earns 1★ per level of each adjacent sawmill, windmill or forge, up to 8. A producer's level is the number of adjacent huts / farms / mines.