The first time that I got in touch with Equal7 was on the design competition ath the IPP in Berlin.
Krasknoukhov, the designer of the puzzle, introduced it personally to me.
It is a 3-dimensional sliding puzzle and is very similiar to the hungarian 2 x 2 x 2 Varikon Puzzle,
which was very popular in the eighties.
Equal7 consists of seven red dices which are enclosed in a transparent plastic cube of the size 2 x 2 x 2.
All seven dices are identical, but have different orientations.
They are also different from an ordinary dice in regards to their numeration:
Instead of having six points on one side, they have a blank side.
Moreover, the sum of two opposite sides equals always five.
The plastic cube container has a special shape on one corner so that it can stand on this corner.
In this position, the cube container on the top has dice points with either one, three or five points.
If Equal7 is standing on the corner, then the observer gets the impression that it consists out of eight dices.
There are four different tasks to Equal7.
The aims are to shift the dices in such a way that all sides show either 10, 11, 12 or 7 points.
Thereby, the dices are moved by overturning the 2 x 2 x 2 cube container.
The tasks can be easily solved within a half hour.
Before moving the dices to solve the puzzle,
I am thinking about the position in which the dices should be in the final stage.
I like the puzzle design very much in spite of strong similarities to the Varikon Puzzles:
As dice points are used instead of colours, the puzzle presents a packing problem at the beginning.
Before moving the dices, you first think about the position of the dices to each other.
A further advantage is that you can solve four tasks at once instead of one.
Due to the trick with the dice points on one corner, the puzzle looks very aesthetically
and harmonic when standing on its corner.
Equal7 is well suited for adults as well as for children.
The problem is easy enough for children so that they can enhance their analytical skills.
But the puzzle is also a challenge for adults.