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Nine Men’s Morris

By David, 30 October 2015 Activity

A grid of three concentric squares. Three pieces are lined up along a line, and a piece of a different colour is being removed.

If you get a line, you can remove one of your opponent’s pieces!

You will need

  • A morris board. You can download a morris board here.
  • A set of nine white counters and a set of nine black counters
  • Someone to play against

The rules

  1. Give each player a set of nine matching counters.
    The same board. A line of three is finished. Three pieces of the other colour are in a line and cannot be removed. the fourth counter of this colour is removed instead.

    If possible, take counters that are not in a line of three.

  2. Choose who gets first go.
  3. Take turns putting one piece down on an unoccupied circle.
  4. If you get three of your counters along one of the drawn straight lines, you can remove one of the opponent’s counters from the board. Once the counter is removed from the board, it is out of the game.
  5. When removing an opponent’s piece, you have to take one that isn’t in a line of three, unless there is no other option.
    Lots of counters on the board. A piece slides from one intersection to an adjacent one.

    Once all the pieces are down, you can slide a piece along a line to an adjacent unoccupied space.

  6. Once you have placed all nine of your pieces, on your next turn you can slide one of your pieces along a line to an adjacent, unoccupied circle. Once again, if that completes a line of three counters, you can remove one of the opponent’s counters from the game.
  7. When your opponent only has two counters left, you win!
  8. If you can’t move any of your pieces on your turn, you lose!
  9. If the pieces on the board are in exactly the same places as they were on an earlier turn, the game is a draw.
    There are only two white counters left.

    When your opponent only has two counters, you win!

Hints

  1. If your opponent is threatening to make a line of three, see if you can block it.
  2. Taking the opponent’s counters is sometimes a good way of blocking them.
  3. You can move your counter out of a line of three and then move it back on the next turn to complete the line again and remove an opponent’s piece.
  4. One very powerful setup is to be able to move a piece back and forth between two lines, completing one and breaking the other each move.

Extra rule

Try adding a flying rule.

  • When you have only three counters left, you no longer have to slide along lines. On your turn you can move one of your counters to any unoccupied circle on the board.

What’s happening?

Nine Men’s Morris is an ancient game, at least 2000 years old. Archaeologists have found morris boards engraved in Roman ruins.

In 1996, a researcher named Ralph Gasser used computers to look at Nine Men’s Morris. He calculated all the possible board positions, and then worked out the best moves for each. In the end, he calculated that if each player played perfectly, the game would be a draw.

More information

Play Nine Men’s Morris online
Solving Nine Men’s Morris (very advanced PDF)

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