Zobrist Cube

## Description

A 3x3x3 cube consists of 27 single cubelets. Polycubes can be made of from 1 to 5 cubelets and are the shapes that everyone remembers from spatial IQ tests. The challenge presented is to assemble 6 or 7 different polycubes into a 3x3x3 cube. Sounds easy? Some of the combinations are easy and fun for all ages, but there are some devilish combinations that will truly test your spatial skill. The free smartphone app comes with 40 puzzles at different skill levels.

The pieces for a particular combination are presented sequentially for assembly into the whole cube. When inserting one piece, there are control arrow touch pads for moving and flipping the piece into its location in the solution. There is a help touch pad to show a good solution location for the current piece.

A timing function measures your skill at the full solution and the best time is kept for each puzzle. Use of the help button turns off the timing, but of course you can start over to get a recorded time. The best world times can be inserted into the smartphone game scoring utility using your nickname.

TUTORIAL

The best way to learn the game is to go directly to a puzzle. Do this by going to the home screen which has the word START pulsing in color and intensity. Push the start button, which takes you to the SELECT LEVEL screen. The five choices differ only by the number and sizes of polycubes used to assemble the 3x3x3 big cube. So you can select any of the choices here, for example, select Easy Set I.

Going to Easy Set I, you will see eight puzzles represented by the letters of the pieces for each particular puzzle. The puzzles on the top (in blue) are unlocked and you can play those puzzles by touching the desired blue bar. The magenta puzzles have a lock symbol and you cannot select them yet. They will become unlocked as the earlier puzzles are solved.

Now selecting one of the puzzles will show the puzzle pieces near the top of the screen in a suggested order of solution. The first piece will already be placed in a solution location, and the second piece will be placed BUT NOT NECESSARILY IN A SOLUTION LOCATION. Your challenge is to move the piece into a solution location. Moves are accomplished with the set of five arrows at the bottom of the screen. Two of the arrows shift the piece laterally. Notice that the shift is always in one direction, the direction of the arrow. When the piece gets as far as it can in the direction, it cycles backwards to the other extreme of that direction. This allows one arrow to move the piece in either direction. The curvy arrows are for flips and rotations and also use one direction with cycling. Altogether, this allows five arrows to do the work of ten.