More on the theme of overlapping octagons.

The colour combinations with designs like these are almost endless, and provide the perfect opportunity for creating transparency effects.

Even the simpler, more regular patterns create lots of interesting little secondary shapes. Squares within squares within squares.

As with my previous octagon-based designs, these ones could be made using mostly squares, half-square triangles and quarter-square triangles. Setting on-point might be easier, as it would require mostly squares, quarter-square triangles and rectangles.