The Rubik's cube is a famous mind game that's probably among the first physical puzzles which people attempt. And it often seems impossible when up against the clock. Now it has become a brainteaser , with an image showing many of the coloured cubes looking the same. However, there is an odd one in the bunch and it must be spotted in 30 seconds. Only those with sharp eyes will be successful in spotting it. The brainteaser was devised by online gaming experts MrQ who teased puzzlers saying it