Engineering Pune, successfully solved Rubik's cube in 30 minutes on college ground. The successful attempt is recorded in the Limca Book of Records. The college will submit the relevant data, witness statements and video of the event to Guinness authorities. Top 10 solvers by single solve Top 10 solvers by average of 5 solves Variations There are many different variations of Rubik's Cubes. The most common class of variants changes the "order" of the cube, defined by the number of layers in each dimension or equivalently by the number of pieces along each edge (including corners). The 2×2×2 (Pocket/Mini Cube), the standard 3×3×3 cube, the 4×4×4 (Rubik's Revenge/Master Cube), and the 5×5×5 (Professor's Cube) are the most well known, as they are all available under the official Rubik's brand. The WCA sanctions speedsolving competitions for cube orders up to 7x7x7. These "big cubes" represent about the limit of practicality for the purpose of competitive speedsolving, as the cubes become increasingly ungainly and prone to mechanical failure (such as "popping", where one or more pieces become dislodged from the puzzle), and average solve times increase quadratically with each larger order, in proportion to the number of total "facelets" of the cube. Even larger cubes based on the V-Cube patents are commercially available to the mass-market from non-licensed manufacturers, most of them Chinese firms who also produce popular cubes designed for speed-solving. The 17×17×17 "Over The Top" cube (available late 2011) was until December 2017 the largest commercially sold cube, and the most expensive, costing over US$2000. A mass-produced 17×17×17 was later introduced by the Chinese manufacturer YuXin. A working design for a 22×22×22 cube exists and was demonstrated in January 2016, and a 33×33×33 in December 2017, though designs this large are not currently mass-produced. Chinese manufacturer ShengShou has been producing cubes in all sizes from 2×2×2 to 15×15×15 (as of May 2020), and have also come out with a 17×17×17. The largest currently mass-produced cube is 21x21x21, made by MoYu beginning in 2021, and costing between $1100 and $1600. There are many variations of the original cube, some of which are made by Rubik. The mechanical products include Rubik's Magic, 360, and Twist. Also, electronics like Rubik's Revolution and Slide, were also inspired by the original. One of the 3×3×3 Cube variants is Rubik's TouchCube. Sliding a finger across its faces causes its patterns of coloured lights to rotate the