Connect numbered nodes in order while filling every cell of the grid.
Place one queen per row, column and color region — no two queens may touch.
Fill the grid with suns and moons — balance every row and column and satisfy all constraints.
Fill the grid so each row, column, and sub-box contains every digit exactly once.
Reveal every safe cell by deducing where the hidden mines are — no guessing required.
Use the row and column number clues to fill the grid and reveal a hidden picture.
Place two stars in every row, column and colour region — no two stars may touch.
Place light bulbs to illuminate every white cell — numbered black cells say how many bulbs touch them.