Perplexus

Perplexus is a three dimensional maze puzzle enclosed inside a clear plastic sphere, in which a player tilts and rotates the ball to guide a small steel marble along a raised track through a series of numbered obstacles. It was invented by college professor Michael McGinnis together with toy designers Brian Clemens and Dan Klitsner of the San Francisco firm KID Group, who began developing the concept in the late 1970s and refined it into a finished design by 2000. The puzzle was launched under the name Superplexus in 2001 before being rebranded as Perplexus, and it is manufactured by Perplexus LLC, which has been a wholly owned subsidiary of Spin Master since 2017. Different versions of the puzzle vary sharply in difficulty, from beginner models with around thirty track steps to advanced designs with well over two hundred, and some tracks briefly drop the marble into a small cup or rim to make use of the sphere's three dimensional shape rather than a flat maze surface.