Rubix Cubes Left: A Rubik’s 2x2 (Pocket Cube/Mini Cube). The logo tile is a giveaway. The 2x2 is the simplest official Rubik’s Cube variant. Right: A Void Cube (3x3 Void Cube) or a similar black-bodied void-style cube. The missing center/core area creates holes through the puzzle, which is the defining feature of a Void Cube