The purpose of Lines is to gain points by aligning at least five or more balls of the same colour horizontally, vertically, or diagonally. Balls can only be moved horizontally and vertically and for every turn three more balls are added to the grid.

When five or more balls of the same colour are aligned they are removed from the board and another move is allowed before more balls are added to the grid.

The game ends when the grid is filled and no more moves are possible.