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Home * Games * Awari

Front side of owari game variant [1]

a variation of the two-player abstract strategy mancala board game Oware or Awele. Awari was played five times at Computer Olympiads, from the 1st Computer Olympiad in 1989 until the 5th Computer Olympiad in 2000.

It's a Draw

In 1990, Victor Allis, Maarten van der Meulen, and Jaap van den Herik first applied retrograde analysis to Awari [2], in 2000 and 2002 further elaborated by Roel van der Goot [3] and Thomas Lincke respectevely [4]. Awari was strongly solved by John Romein and Henri Bal in 2002 - either side can force a draw [5]. They developed a program that computes the best move and eventual outcome for all 889,063,398,406 positions that can possibly occur in Awari and further published a Java applet to play against their Awari Oracle, a potentially infallible opponent. The database requires 778 GiB stored on disk and was generated using parallel retrograde analysis with a cluster of 72 dual PIII @ 1 GHz with 1 GiB of main memory each, connected through Myrinet, which took 51 hours [6].


Owari or Awari is played on a board that contains two rows or depending on the layout, sectors of six pits called "houses", in which seeds (pieces or stones) are kept. Each player owns one of the rows. The game starts with four seeds in each pit. When a player is to move, he chooses one of his own nonempty pits, takes all seeds from it, and sows them one by one, counterclockwise over the remaining pits, skipping the emptied pit if there are more than 11 seeds. If the last seed ends in an opponent’s pit and contains two or three seeds after sowing, they are captured. If the second last pit holds the same conditions, they are captured as well, and so on. The objective of the game is to capture more than 24 seeds. The player must give the opponent a countermove, unless no such move is available. If a player cannot move, the remaining seeds are captured by the opponent. A repeated position leads to an even division of the remaining stones, ending the game [7]. The rules slightly differ from one country to another. For example, the "grand slam rule", which states what happens if all opponent’s pieces are captured in a single move (if allowed at all !) comes in many variants. The rules of computer-aided play of Awari concerning repetitions, captures and leaving the opponent without countermove [8] were defined by Victor Allis, Maarten van der Meulen, and Jaap van den Herik in 1991 [9]

Computer Olympiads

See also

Selected Publications


  • Jean Retschitzki (1989). Evidence of Formal Thinking in Baoule Awele Players. in Heterogenity in Cross-cultural Psychology. Swets Zeitlinger, Amsterdam

1990 ...

2000 ...

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