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Skyline Builder is the Skyscrapers puzzle: place buildings of different heights in a grid so that the number visible from each edge matches the clue. A taller building hides everything shorter behind it, so each clue constrains the arrangement in a way that is surprisingly powerful.
Read the clues around the edge of the grid.
Each clue says how many buildings are visible from that direction.
Place heights so every row and column uses each height once.
Taller buildings hide shorter ones behind them.
Satisfy every clue to complete the grid.
Constraint satisfaction — deducing an arrangement from indirect information. It is the same reasoning as Sudoku with a visibility rule layered on top.
A clue of 1 means the tallest building is immediately there. That is the strongest clue in the puzzle and it should always be your first move.
A clue equal to the grid size forces a strictly ascending row — the only arrangement where every building is visible.
High clues mean a low first building; low clues mean a high one. Work from the extremes inward.
Once a row is fixed, propagate the eliminations through its columns immediately.
Looking along a row from one edge, you see a building only if every building before it is shorter. A clue of 3 means exactly three are visible from that side.
Yes — each height appears once per row and column, exactly as in Sudoku. The visibility clues replace the box constraint.
Always a clue of 1, then a clue equal to the grid size. Both determine an entire row or column immediately.
No. Every puzzle is solvable by deduction alone.