5- The objective of the game
In the original game of chess, the match ended as soon as a king was captured. The occasional oversight probably led to a few games concluding a little sooner than they should have and so it was the Persians who, in the 8th century, introduced the idea of warning the opponent whenever their king was under a direct threat of capture, a condition known as “check”. (Some people claim that the practice had already existed in India.) The Persians would take it a whole step further when they later introduced a rule making it illegal to place or leave one’s king under a direct attack. And if it did happen inadvertently, the now “illegal” move had to be taken back.
Although this new rule did protect chess players from their worst blunders, it did not otherwise affect the way the game was played. To win, one still had to force the opponent into a situation where their king could not escape capture. The opponent was then said to be “mate” and doing so won the game. It is true that the kings were no longer captured but once a king was mate, this was hardly more than a formality.
In Chess 99, as per the original rules of chess, the objective of the game is to capture the opposing king and it is perfectly legal – although usually ill advised – to make a move that places or leaves one’s king in check. One does not warn the opponent that their king is under attack so that it becomes the responsibility of the players to be fully aware of the game situation at all times. Experienced players will know when their king is in check so that this rule will make little difference to them. As for novice players, they will quickly learn to always look out for their king, perhaps something they should be doing anyway.
Players used to announce “En garde” (a French expression meaning “On guard”) to indicate that the queen was under a direct attack. The practice was largely abandoned in the 19th century forcing players to pay close attention to their queen, the most powerful piece of the game and certainly one that nobody would want to give up by accident. In Chess 99, players need do the same for their king.
The first immediate consequence of this return to the original rules is that as long as a piece is played according to its own particular movement, the move is always legal. This is unlike standard chess where an illegal play can well happen and if it goes unnoticed the game itself becomes “illegal”. A situation in Chess 99 where, for example, a king would be placed in check and then out of check without anyone ever noticing would certainly not be a memorable game, but it would still be a “legal” game.
Example of what would be, in standard chess, an illegal play:
Black plays the pawn to d5 exposing their king to a check from the bishop on a3. White, who could have captured the king and won the game, does not notice and plays the pawn to c5 blocking their own check. Not a game to remember but it is nonetheless legal.
Please note that players may still warn their opponent that their king is under direct attack, either as a courtesy or to prevent a premature termination of the game, if they wish to do so. However, players should not be permitted to take back a play because the move accidentally put their king in check. Such action would definitely be against the rules.