Rubik's Magic

Rubik's Magic™, like Rubik's Cube™, is a mechanical puzzle invented by the Hungarian sculptor and professor of architecture Ernő Rubik and first manufactured by Matchbox in the mid-1980s.

The puzzle consists of 8 black square tiles arranged in a 2 x 4 rectangle; diagonal groves on the tiles hold wires that connect them, allowing them to be folded onto each other and unfolded again in two perpendicular direction (assuming that no other connections restrict the movement). The front side of the puzzle shows, in the initial state, three separate, rainbow-coloured rings; the back side consists of a scrambled picture of three interconnected rings, and the goal of the game is to fold the puzzle into a heart-like shape and unscramble the picture on the backside, thus interconnecting the rings.

Numerous ways to accomplish this exist, and experienced players can transform the puzzle from its initial into the solved state in less than 5 seconds. Other challenges for Rubik's Magic include reproducing given shapes (which are often three-dimensional), sometimes with certain tiles required to be in certain positions and / or orientations.

In 1987, the so-called "Master's Edition" of Rubik's Magic was published; it consisted of 12 silver tiles arranged in a 2 x 6 rectangle, showing 5 interlinked rings that had to be unlinked by transforming the puzzle into a shape reminiscent of a W. In the late 1990s, the original version of Rubik's Magic was re-released by Oddzon, this time with yellow rings on a red background; other versions (for example, a variant of the original with silver tiles instead of black ones) were also produced, and there also was a strategy game based on Rubik's Magic.

Professor Rubik holds both a Hungarian patent (HU 1211/85, issued March 19 1985) and a US patent (US 4,685,680, issued August 11 1987) on the mechanism of Rubik's Magic.

Details

Warning: Wikipedia contains spoilers.

A Rubik's Magic chain

It can be seen that the total number of 2 x 4 rectangles that can possibly be created using Rubik's Magic is only thirty-two; these can be created from a total of eight distinct chains. The easiest way to classify chains is by the means of the middle tile of the puzzle's finished form (the only tile that has segments of all three rings) and the tile next to it featuring a yellow/orange ring segment (the indicator tile).

Every chain either has the middle tile on the outside (O) or the inside (I) of the chain; if it is arranged so that the indicator tile is to the right of the middle tile, then the position of the ring segment on the indicator tile can either be the upper left (UL), upper right (UR), lower left (LL) or lower right (LR) corner. The position and orientation of the remaining tiles is then determined by the middle and indicator tiles, and a total of eight distinct chains (OUL to ILR) is obtained, although the naming convention is not standardized.

Similarly, the 2 x 4 rectangle forms of the can be categorized. Each of these forms has exactly one chain associated with it, and each chain yields four different rectangle forms, depending on the position of the edge where it is folded with regard to the middle tile. By concatenating one of the numbers 0, 1, 2 or 3 to the chain's name, depending on whether the number of tiles to the right of the middle tile before the folding edge, a categorization of the rectangle forms is obtained. The starting position, for example, is rectangle form OUR2.

A similar classification can also be obtained for the heart-shaped forms of the puzzle, of which a total of 64 exist.

Solving the puzzle

As soon as one understands that only thirty-two different rectangle forms exist, it is easy to solve the puzzle: the back side of OUL1 already contains five of the tiles in the right positions, so after getting to that form, all that still needs to be done is fixing the remaining three tiles.

To get from the start (OUR2) to OUL1, one first needs to fold the two outer colums of the puzzle onto the middle ones (obtaining a 2 x 2 x 2 package); then, the lower row is folded onto the upper one, and the puzzle is unfolded again, now in form OUL0. Folding up the puzzle again into a chain and rotating by one tile then yields OUL1.

To finish the puzzle, the back side is placed face up now so that Professor Rubik's signature is at the lower right; then, the rightmost column is folded onto the neighbouring one, the upper tile (which used to be the corner of the rectangle form) is folded down, the rightmost column is folded to the left again, the two pieces at the bottom are folded up and the middle piece of the upper row is folded right. After folding the remaining two pieces upwards, the final heart shape is obtained, showing the three connected rings.

With some practice, this solution can be done and undone in less than five seconds each.

External links

• Some Rubik's Magic shapes to reproduce