A solid cube with holes on the surface, hiding a tunnel maze inside. You can't see the tunnels, only the openings. Tilt it and listen for the marble to find its way from one opening to another.
Comments
belforn•59m ago
As a market test, 3DPrinted orders and downloadable files are available at Thangs, in 3 flavours: Intense / Impossible / Insane ;)
belforn•59m ago
site -> https://www.cunicode.com/works/bbmm