Instructions

• New features: See notes near bottom of this web page.
• Rules of the game
  • The object is to capture your opponent's king, moving pieces determined by dice rolls.
  • An initial roll determines which player goes first.
  • During your move, you must move a piece of the type shown on the randomly rolled die. (Even if you don't want to. You may even be forced to move into "check".)
  • The concept of "check" is different, in that you may be in check, but your opponent will win only if the checking piece appears on the subsequent roll.
  • The Free Pawn Push Rule If you cannot move a piece that appears on the roll (because you have none or because such pieces are stuck [but not because of any check considerations]), then you may push any pawn one square forward, except you may not promote. (Thus you may not double move, may not promote, and may not capture with such a free pawn push.)
  • If you cannot even make a free pawn push, then you pass your turn.
  • Castling is a king move (not a rook move). You may castle out of check, through check, or even into check, since "check" does not really exist.
  • Capturing en passant is permitted only when a natural pawn move is rolled immediately.
• Selecting players and levels
  • You may play human versus human, human versus computer, or computer versus computer
  • You may change levels before a game, or during a game during a human's move or when the game is paused. Note that you must wait for the current move to be executed before the level change takes effect.
  • Computer Level 0: moves randomly, unless the king can be captured
  • Computer Level 1: will try to give check and stay out of check
  • Computer Level 2: also considers captured material
    • Level 2.1: slight improvement, with consideration of direction of king moves
  • Computer Level 3: Considers the number of checks and material value
    • Level 3.1: same, but with less randomness in move selection
    • Level 3.2: Prefers to keep king back, unless endgame.
    • Level 3.3: Considers that a second piece of the same type is not as valuable as the first piece of that type.
  • Computer Level Ply0: Calculates approximate probability of winning based on checks and material. Takes into account of multiple checks, ways getting out of check, and whose move it is. Takes into account of pieces under attack.
  • Computer Level Ply0d: Same, but with almost zero random perturbation in selection of move.
  • Computer Level Ply1, Ply1d: Considers all possible response moves by opponent. Takes about 8-10 seconds on a "slower" computer. A decent level to play.
  • Computer Level Ply2, Ply2d: Does a ply 2 search. Takes about 8-10 seconds on a 200 MHZ computer. Highly recommended if you have the equipment. It is often more efficient on a low-level applet runner (as opposed to a full web browser), thus Ply2 is feasible even on a 60MHZ computer in such cases.
  • Computer Level Ply3, Ply3d: Does a ply 3 search. Takes too long in the opening. You may wish to try this out in an endgame. (This may not be an issue in the future with faster computers.)
• Abort game, to Pause, to Continue
  • These buttons should be self-explanatory
• Show Prob
  • This options shows the static evaluator probabilities (with any higher ply probabilities in parentheses).
• Style points (only for amusement, does not count towards the game):
  • the following are considered stylish (improving or hurting your position aside)...:
    • Castling
    • Capturing en passant
    • Underpromoting a pawn
    • Forcing your opponent to move into check
    • "The Lift". Capturing an opponent's piece by having ALL 6 possible pieces attacking it.
• Version 2.0 features:
  • Seeding the random number generator:
    • This features allows you to play a fixed sequence of rolls as determined by the seed.
    • This allows a "duplicate" competition.
    • Just check the seed checkbox and type in a number (can be a long integer).
  • The replay feature:
    • Allows a stepping through of a previous game.
    • You may use the pause, undo, forward buttons to step through the game.
  • The undo feature:
    • You may undo moves.
    • You must first pause the game.
    • You may also undo undos by using the forward button.
• Version 3.0 features:
  • Loading and replaying games:
    • Hit the "Load names" button to load names of available saved games.
    • Then select the desired game.
    • Then hit the "Load game" button to load and replay the game.
    • The games are stored on the web server and not in the applet, so you must be online for this feature to work.
• Known bugs from previous versions [fixed in later versions]:
  • In version 1.5, the advanced pawn incentive was not implemented correctly (thanks to a program typo), a somewhat crucial disadvantage in the endgame. Fixed in version 1.7.
  • In version 1.7, a rare error occurs when a single piece gives "checkmate" all by itself (rare indeed). Fixed in version 1.8.