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WCC is capable of playing every position with 7 or fewer pieces perfectly.

What does this mean? When WCC is in a winning position, it will always converge on the win in the quickest manner possible. It knows exactly how many moves are required to reach the last move of the game for every position in its database. So, when WCC plays the winning side, it generates every legal move, then queries the database to get the total number of moves remaining in the game after the move is made. WCC then selects the move leading to the quickest win.

If you set up WCC to play a position that is a loss, it will query the database and select the move that leads to the most distant loss possible, thereby dragging out the game.

Is it possible to be in a won position and not win against WCC? Yes! Can WCC be in a loss and still hold a draw? Yes! Is it possible for WCC to be in a won position in its PPL database and not win? No!

WCC played two friendly experimental games with the Wyllie program to test how the perfect play database could defend a "lost" position. One position was the most distant win possible in which the losing side cannot set up a Fourth Position draw. This position is hard for a human to win, but because the path to the win is punctuated with positions in which there is only one move to win, the Wyllie program was able to eventually find the win.

In the second game, WCC again played the losing side of a 7-piece position, and Wyllie was not able to win the game.

WCC also played the Kingsrow program in three experimental games. On the winning side, Kingsrow was unable to win against the powerful perfect play lookup database. At the point where Kingsrow allowed the draw, WCC took over, now playing the strong side against Kingsrow. WCC was able to win this game easily. Kingsrow programmer Ed Gilbert found some code in his program that was in need of changing to avoid a "repetition draw," so about two weeks later a third game was played. Kingsrow was unable to win that game either.

You might be aware of what is referred to as a "conversion" database. How does a "conversion database compare to a perfect play database? The answer is: A conversion database is vastly inferior to a perfect play lookup database. In fact, a conversion database can be worse than no database at all when it comes to playing a position!

A classic example from the 3-piece database demonstrates the extreme deficiencies of a conversion database.

Every novice player on the planet can immediately identify with a casual glance that 15-18 is the best and quickest move to win, forcing the king up against the side of the board and capturing him in only five moves. But a conversion database will prefer to "convert" by advancing the checker with 21-25??? and crowning on the next move, leading to a long, drawn-out win as the opponent's king escapes into the double corner.

The reason for this is that a conversion database always thinks that the best way to win is to either trade pieces or promote kings (that is, to "convert" to a position with a different combination of pieces). As long as it preserves the win, a conversion database will blindly make foolish moves. To a conversion database, the move 15-18 takes too long to convert, even though the conversion is a game-ending win, which it does not know, unlike a PPL database. The move 25-21 converts the checker into a king more quickly than 15-18 converts to the game's conclusion, therefore, the foolish and wasteful move 25-21 will be played by a conversion database. If the conversion database were turned off in this position, a simple search by the program would find the best move instantaneously. Thus, in this example, a conversion database is far worse than no database at all!

The major difference between the perfect play lookup (PPL) database and the conversion database is this: The PPL database actually knows when the game is over! For this reason, no matter where you are in a game, the PPL database will always converge on wins most quickly, and push losses as far away as possible, often frustrating the opponent into conceding a draw.

WCC's PPL database is the only database that plays perfectly every time.