Kalah, also called Kalaha or Mancala, is a game in the mancala family invented by William Julius Champion Jr (USA) in 1940. This game heavily favors the starting player, who will always win the three-seed to six-seed versions with perfect play. This game is sometimes also called "Kalahari", possibly by false etymology from the Kalahari desert in Namibia.
As the most popular and commercially available variant of mancala in the West, Kalah is also sometimes referred to as Warri or Awari, although those names more properly refer to the game Oware.
An electronic version of the game, called Bantumi, was included on the Nokia 3310. The handset went on to sell 126 million units making Bantumi the best selling version of the game.
The game requires a Kalah board and 36 seeds or counters. The board has six small pits, called houses, on each side; and a big pit, called a Kalah or store, at each end. Many games sold commercially come with 48 seeds or counters, and the game is started with four seeds in each house.
The object of the game is to capture more seeds than one's opponent.
The player begins sowing from the highlighted house.
The last seed falls in the store, so the player receives an extra move.
The last seed falls in an empty house on the player's side, with seeds in the opposite house.
The player captures the 4 seeds and ends his/her turn.
At the beginning of the game, three seeds are placed in each house.
Each player controls the six houses and their seeds on his/her side of the board. His/her score is the number of seeds in the store to his/her right.
Players take turns sowing their seeds. On a turn, the player removes all seeds from one of the houses under his/her control. Moving counter-clockwise, the player drops one seed in each house in turn, including the player's own store but not his/her opponent's.
If the last sown seed lands in the player's store, the player gets an additional move. There is no limit on the number of moves a player can make in his/her turn.
If the last sown seed lands in an empty house owned by the player, and the opposite house contains seeds, both the last seed and the opposite seeds are captured and placed into the player's store.
When one player no longer has any seeds in any of his/her houses, the game ends. The other player moves all remaining seeds to his/her store, and the player with the most seeds in his/her store wins.
It is possible for the game to end in a draw, with 18 seeds each.
A common, more challenging variation is to begin with four, five or six seeds in each house, rather than three. Four-, five- and six-seed Kalah have been solved, with the starting player always winning with perfect play, as in three-seed Kalah. Thus some web sites have implemented the game with the pie rule to make it fair.
An alternate rule has players sow in a clockwise direction, requiring more stones to be sowed in a single turn to reach the store.
The "Empty Capture" variant modifies the rules to prohibit a player from capturing seeds from his/her opponent when landing in an empty house -- i.e., only the last sown seed is placed into the store.
An alternate rule does not count the remaining seeds as part of the opponent's score at the end of the game.