Machines are full of hard edges, chrome and painted panels, so pieces snap into recognisable assemblies quickly. Vintage vehicles are the pick of the category — the paintwork carries reflections and wear that give even a flat door panel something to grab. Rows of parked bicycles or boats in a harbour behave like a pattern puzzle and are noticeably harder.
Panels, badges and lettering give you fixed points, and the reflections on bodywork are more useful than they look — a highlight running across a wing is a line you can follow. The difficulty is usually the surface the vehicle is standing on: tarmac and studio backdrops are both flat fields, so treat them the way you would a sky.
Difficulty: Easy to medium. Large flat body panels are the sticking point. Every picture here is graded automatically by how much its neighbouring pixels differ, rather than by subject — why that is the thing that matters.
Pick any picture below, choose anywhere from 12 to 2000 pieces, and play free in your browser. Share one link to solve it with friends on the same table, or use a photograph of your own instead. Browse every category.