How to play Solitaire (or le Morpion)

The solitaire rules, by Alexis Wilke. Feel free to copy this document by any means you can imagine, please, make sure you include the images in your copies. Give it to whoever you want! And don't forget to give a link to the page.

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The board at the start
One move
Play the game
Illegal moves


the startup cross
an horizontal move
a vertical move
a diagonal move
end of game with 83 crosses
sample of illegal moves

The board at the start

This solitary game, also called le morpion in French, starts with a cross composed of 12 groups of four crosses (see Fig 1.). These are used to add new crosses by drawing lines.

Fig 1. the startup cross

One move

To make progress, you add new crosses. A new cross is added when you can draw a line between five cross emplacements where one of the emplacement is empty and the four others include a cross each. All the crosses you use to draw a line can't themselves have been used to draw the inside of a previous line (i.e. two consecutive emplacements can't already include a line). You can draw lines in all four directions (horizontally -- see figure 2, vertically -- see figure 3 and in diagonals -- see figure 4).

Fig 2. an horizontal move

Fig 3. a vertical move

Fig 4. a diagonal move

Play the game

Voila! You know how to place one cross, now you can place as many as you wish. The game ends once you can't place a new cross anymore. A very bad play stops around 41 to 43 crosses. A very good play stops around 95 to 97 crosses. The best is what I'm looking for an my computers didn't find it yet. 8-)

The following is an example of 83 crosses. You can see that the cross 4 uses the cross 2 to be inserted. Similarly, the cross 5 uses the cross 1. Then, the cross 6 uses the crosses 4 and 5 (all of these are close to the bottom of the startup cross). The computer generated this game using the software included on SourceForge.

Note how some crosses are reused as these are the tip of a line. You can see this phenomena with cross 37. The cross 42 used cross 22, a startup cross, cross 41 and 37. Then later in the game, cross 70 is drawn using cross 37 again (the tip of the line created to add cross 42), cross 31, a startup cross and cross 69. Crosses 36, 43, 46, 59, 64 and many others also use a tip.

Fig 5. end of game with 83 crosses

Illegal moves

It is illegal to reuse two crosses which have already been used to draw a line in the same direction that your new line would be. The following figures show you illegal examples. The purple crosses marked a and b are illegal because they reuse crosses already used to draw the 3rd and 4th crosses respectively. The parts being illegally reused are marked with a white circle.

Fig 6. sample of illegal moves