Behold the Screwball, a featureless sphere with a secret way of opening and a compartment within. Screwball is only solved once you find the hidden trinket. You'll need to use your wits and powers of observation to deduce the solution. Note that although color is purely aesthetic, semi-transparent colors may show a tiny bit of the infill, giving some minor hints of the mechanism inside. They are however, not susceptible to cheating via standard brightness lighting.

The puzzle is UV reactive. Under normal sunlight it is already quite bright, but it fluoresces like a glowstick under blacklight.

• See at Puzzle Master