The house book
Ten worlds have lost their colour. Solve a world’s puzzles to bring it back, then beat its boss to open the next. Each puzzle shows its rules before you start; pencil marks, candidates, undo and gentle hints are there when you want them.
Keys Digits enter · Arrows move · Shift/Ctrl add to selection · Z X C V switch mode · Shift = corner, Ctrl = centre while held · Space cycles · Delete erases · N shows candidates · G colour wash (every digit in its own colour) · L digits left · Ctrl+Z / Y undo, redo · P pauses
Arrow keys move the cursor. Type a digit to fill the cell. Hold Shift for corner marks, Control for centre marks. Delete clears. The board below lists every cell.