I made a Super Mario (from Super Mario 3, my favorite NES Mario game) out of stained oak cubes. I basically stole this idea from pinterest https://www.pinterest.com/pin/28429041373312165/?from_navigate=true

Cutting 1x6 pine boards in the table saw to be exactly 1" strips.

A couple strips cut

All strips cut - lots of burn marks from the table saw. Each strip had to be sanded down until all marks were gone.

A 2x4 fence was used to cut the cubes to exactly 1" to match their width.

Cubes beginning to surface

So many cubes

Red cubes stained

All cubes organized

Black cubes stained

Halfway! I ran out of cubes because I didn't count ha

Finished and mounted on the wall - 3 coats of polyurethane.

I cut a piece of 1/4" plywood with my jigsaw to act as a backing-board for the cubes. Each cube was then glued to the plywood. The trick here is to glue the perimeter first, and then worry about the inside cubes.