BUDAPEST -- Thirty-five years after inventing the world's best-selling mechanical puzzle, Erno Rubik is hoping Thursday's launch of the Rubik's 360 will be another mind-bending hit.

Launched at an international toy fair in Germany, the new game features six balls inside three transparent spheres and the challenge is to move the balls from one sphere to the other.

Presented to toymakers and distributors at a fair in Nuremberg, the Rubik's 360 will not be available to the public for several months, Rubik's company told AFP in Budapest.

Rubik invented his famous cube, originally called the "Magic Cube", in 1974.

Exported from Hungary from 1980 onwards, the Rubik's Cube fast became an international sensation and has remained one of the top-selling toys in the world ever since.