I've seen some other chess programming posts and was pleased that others in this community share my interests. As an introduction, I've been playing chess for about 1 year and am not very good at it. That being said, I still have found a very satisfying hobby in using the game of chess for fun programming projects.
Recently, I was introduced to a new variant of chess, called S-Chess (or Seirawan Chess, after Grandmaster Yasser Seirawan who co-created the game). The motivation behind this new game is that theoretically the game of chess is (probably) a draw. After a game of perfect play by two Grandmasters, the game will likely end in a boring 1/2-1/2 result (maybe you recall the 2016 World Championship). The solution to this dilemma is S-Chess, an exciting game which explores new powers on the chess board.
S-Chess introduces two new pieces onto the chess board: the Elephant and the Hawk. These two pieces have movements that are inspired by the power of the Queen. If we consider the Queen as a combination of a rook and bishop, then the Elephant can be thought of as a combination of a rook and knight. The Elephant is theoretically as powerful as the Queen (9 points, though Yasser himself says the Queen is probably more valuable).
The other new piece is the Hawk which has the power of a bishop and knight. This piece is less powerful than the Queen and Elephant but more powerful than a rook. I personally give it a rating of 7 points of material. An interesting feature of the Hawk is that it is the only piece in the game that can checkmate by itself.
Since the traditional chess board only has 8 squares for pieces to start on, you may be wondering how these pieces get introduced into the game. At the start of the game the board is in the normal starting position but now both players start with the Elephant and Hawk pieces in hand. When a player moves a piece (rook, bishop, knight, king, or queen) off the back rank for the first time, they have the chance to immediately summon either the Elephant or Hawk in the vacant square left by the moved piece.
These pieces totally change the game of chess. Opening theory must be completely rethought, as S-Chess can be very punishing for unfamiliar players. These pieces are also special in their endgame theory.
OK, so now that I have you convinced that S-Chess is the next big thing, you may be asking yourself "Where do I play this awesome game?" Well, I found out that the answer is an unfortunate and infuriating "no where!" That's why I took it upon myself to start a new chess project, extending the popular chess.js and chessboard.js libraries to allow the S-Chess variant to come to life. Long story short, I've had great success so far! You can check out my work here.
My goal (which is the same as Yasser's in the video) is for someday to be able to play S-Chess at some of the most popular chess websites. Some things that are still under development are UI improvements, multiplayer play, and an S-Chess AI. If you are a developer interested in helping out, definitely checkout my repo and open a pull request anytime!