a drawing game

I did these with patterns, but you can do it with other images-- figures, colors, etc.
you start by filling in the top horizontal squares and the left vertical squares. You can make those up, take them from somewhere, or have someone else to fill them in.
In the inner squares, you have to make an image that combines the vertical above on top, and the horizontal from the left. If you look at these you can probably figure it out.
One person could start by filling in the top horizontal row, and another person could give the left vertical ones – and each could see how they come up with the combinations.