Rules of Vazir

"Vazir" is a modern twist on the timeless game of Chess. It observes all the rules of classical Chess, and implements the changes listed below in the hope of enriching the original game with new strategies. The original draft offers more generic rules (e.g. element of chance can be any general randomization tool, as advanced as a programmatical function or as primitive of as a dice!).

1. Each piece has a "rank" from 0 to 9.
2. When a piece tries to capture another, the outcome of the attack will be decided using ranks of the two pieces. "Chance of Success" will be calculated as follows:
   • Formula : (a+1)/(a+d+1) , where "a" is the rank of attacker, and "d" is the rank of defender. Once the chance of success is determined, a programmatical random function will be used to determine the result.
3. If a pawn is to be promoted, rank of the new piece will be calculated based on the rank of the pawn, as well as materialistic worth of the piece it is being prmoted to:
   • Formula : max(r - round(w/2), 0) , where "r" is rank of the pawn, and "w" is materialistic worth of the piece it is being promoted to. "Vazir" uses the common 1-3-3-5-9 valuation system. You can find more information on this subject here.
4. Each player has a limited number of tries to capture a piece, before their turn is over. This is called "Moves per Turn", and is indicated by the "MPT" header in R-PGN (Ranked Portable Game Notation). The default MPT is set to 3, but it can be adjusted upon start of a new game.
5. If a king is put in check:
   • If the King has no possible moves, except for taking the attacking piece in order to come out of check, the chance of capture will be 100%
   • If the player tries to capture the attacking piece unsuccessfully, enough times to breach MPT, and king is still in check:
     • If king has no possible moves other than taking the attacker, it is checkmate.
     • If king has possible moves other than taking the attacker to come out of check, the player will be granted one extra move, in which he/she will only be able to move the king out of check.