Chocona
Shade cells so every numbered region contains exactly that many shaded cells and every connected clump of shading is a filled rectangle. Clumps may cross region borders and may touch at corners — only edge contact merges them. Click a cell to cycle shaded → white → empty; right-click erases.
A global law with a local double
"Every clump is a rectangle" sounds like a shape property you can only check by looking at whole clumps. It is exactly equivalent to one local test: no 2×2 window anywhere may contain exactly three shaded cells. Zero, one, two or four are all fine. That gives Chocona its signature backwards move — where most shading puzzles forbid a filled square, here three shaded cells in a square force the fourth shaded, because the only escape from an L-corner is to complete it.
Four rule sets
quota counts a region both ways: number reached — rest white; free cells exactly the missing blacks — all black. corner plays the local double of the rectangle law on every 2×2 window. box makes it global again: a clump's bounding box must fill, a clump with no feasible rectangle left is a contradiction, and a neighbor no feasible rectangle can reach must be white — the moat where the finished rectangle's border will run. probe assumes a color on a cell and watches the rules below refute it.
Two dials on opposite sides of the ledger
The region partition is the setter's dial, drawn freely before any number is printed — borders along the answer's rectangle boundaries make every region all-or-nothing and the counting rule finishes the board alone. The rectangle scale is the answer's dial: the same rules span boards made of 1×1 confetti and boards made of a few large slabs. And unlike this series' connectivity puzzles, a Chocona answer can be built directly — throw random rectangles at the grid and keep the ones that fit. No search, no backtracking, no pathological tail.