Cage Sum Conservatory
Complete the 4×4 Sudoku with digits 1–4. Cage totals constrain the board; digits cannot repeat inside a cage.
Cage workshop lets you seal a whole cage once its distinct digits meet the sum. Sealed cages are protected from accidental edits; Reopen restores editability. Finish by sealing all seven cages as well as satisfying Sudoku. The active cage has gold borders and a live remaining sum.
How to play & accessibility
Complete the 4×4 Sudoku with digits 1–4. Cage totals constrain the board; digits cannot repeat inside a cage.
Tap controls, or Tab then Enter/Space to activate every board cell and action. Arrow keys move where supported. R restarts. Z undoes in calm puzzles. Small numbers identify cells in row-major order. All controls are at least 44 pixels.
Source & original design
Compact original rules study inspired by the listed mechanic, not a full reproduction. New name, board layouts and CSS artwork; no source assets copied.
Source: Killer Sudoku