A grid divided into rooms, four crisp rules, and exactly one correct way to fill in the black, deduction all the way down.
Was this fun?
How to play
The board is split into rectangular rooms. Shade some cells black so all four rules hold at once, and the puzzle resolves to a single valid solution that you uncover purely by reasoning.
A numbered room must contain exactly that many shaded cells; unnumbered rooms are free.
No two shaded cells may touch edge to edge.
Every white (unshaded) cell must connect into one single region.
No straight horizontal or vertical run of white may cross three or more rooms.
Cells glow red the moment a rule is broken; you win when the shading matches the unique answer.
Controls
Desktop: left-click a cell to cycle empty, shaded, then an X mark (known-white), and back; right-click steps the cycle backwards. Use Clear, Hint and New from the toolbar.
Phone & tablet: tap a cell to cycle through the same three states; the X mark lets you flag cells you have proven must stay white.
Game modes
Daily: one shared 5x5, 6x6 or 7x7 puzzle per day for everyone.
Practice: an endless stream of fresh random boards.
Three sizes scale the challenge; a timer and shaded-count track your run for the leaderboard.
Tips & strategy
Use X marks aggressively, flagging forced-white cells narrows where the blacks can fall.
A room needing several blacks in a tight rectangle has very few non-adjacent layouts; solve those first.
Watch the connectivity rule: a black that would wall off a pocket of white is always wrong.
Origins
This is Heyawake — Japanese for "divided rooms" — a Nikoli puzzle that first appeared in Puzzle Communication Nikoli #39 in September 1992.
Its four rules work together: numbered rooms take exactly that many shaded cells, no two shaded cells touch orthogonally, the unshaded cells stay connected, and no straight run of unshaded cells may cross more than one room border.
That last rule is the unusual one and the reason the puzzle is deep. It is the only constraint that reaches across the board rather than staying local, so a deduction in one corner can settle a room three rooms away — which is why Heyawake boards can carry so few numbers and still have one answer.
Roomshade is a free browser version of Heyawake, the classic divided-rooms shading puzzle, where every clue feeds a chain of pure deduction toward one guaranteed solution. Daily and practice puzzles, free in your browser with no download.
A free, original browser game on PlayPendium. No download, no install.
