The goal is to blacken some cells of a grid that all black cells form one orthogonally connected area. A cell with a number indicates how many cells in the region must be blackened. In regions without a number any amount of cells may be blackened (all cells may stay white). There cannot be a run of more than three black or white cells in the grid.
Aqre puzzles require you to fill in black cells on a grid, ensuring that the black cells form a connected area and meet the specified black cell counts within regions, while avoiding long sequences of the same color.