Arimaa is a strategy board game with many similarities but also many differences to chess. It was invented in 2003 by Omar Syed, an American-Indian computer engineer, when a computer first defeated world chess champion Garry Kasparov.
According to the creator, the game is so simple that a small child can play but extremely difficult for a computer.
He even offers a $10,000 prize to anyone who can beat the world champion with his computer. The reason why a computer has a hard time winning is because in each move there are about 17,000 different moves available, unlike in chess where there are about 30. In addition, there are about 64,000,000 ways to set up the checkers in the opening of the game.
Let's take a quick look at the rules of Arimaa: The game is played by two players with gold and silver pawns on an 8×8 grid. The pawns are shaped like animals and there are 8 rabbits, 2 cats, 2 dogs, 2 horses, 1 camel and 1 elephant. The pawns are placed on the first two lines of each player (like in chess) in the order chosen by the player. The winner is the one who gets a rabbit to the opponent's base.
On his turn, each player can make from one to four steps with one or more pawns. Each step consists of moving a pawn one square. The pawns move forward, backward, left or right except for hares which cannot move backward. The strongest pawns "push" the opponent's pawns while there are also 4 trap squares in which if a pawn is trapped it is removed from the board.
Source: www.tro-ma-ktiko.blogspot.gr
