Download Mychess

BenRedic 2020-04-01 0 point

The proto Chessmaster! Mychess was originally developed for and ran under CP/M, hence 1979, at which point MS-DOS did not exist. The version here is basically a 1984 MS-DOS port of the CP/M version, with added graphics. The features and the engine is basically the same.

Mychess was later followed up by Mychess II for a number of 8-bit computers, which basically played the same but had more features. Then it went through a major overhaul and was released as Chessmaster 2000. David Kittinger also went on to produce a number of chess engines for successful computer chess programs and dedicated chess computers.

You can set up a position or set up a game from scratch. You can choose engine strength by limiting number of plies, or by setting a time control. Games can also be printed. There is a rudimentary load/save feature. Game scores can be printed to a printer.

The engine plays a surprisingly competent game of chess, and can certainly measure up against strong early 80s chess programs. Rules of chess are mostly observed, such as castling, promotions and draws, with a few quirks. One quirk is that you are only allowed to promote to a piece that has earlier been taken off the board. So if your queen is still alive, you can't promote to a second queen.

I have also had some issues with the program freezing under MS-DOS. These freezes are reproducable by replaying the exact same games over again: Mychess always freezes at the same moves. Possibly a problem in the MS-DOS port, I have not observed this issue in any of the CP/M versions.

In the following example, Mychess beats White Knight Mk11 for BBC, the accolade winning 1983 precursor to the Colossus chess programs. White Knight thinking at 2 minutes per move, Mychess playing at level 4. White Knight finds itself two pawns down in the endgame, and is duly mated.

[White "White Knight Mk11 BBC"]
[Black "Mychess 1.0 DOS"]
[Result "0-1"]

1.e3
{Apparently, White Knight has no opening book. A very passive move for whites first move.}
1...e5 2.Nf3 e4 3.Nd4 c5 4.Nb5
{Forced to move the knight for the third time in four moves, white quickly finds itself behind in development.}
4...d5 5.N1c3 Nf6 6.Be2 Nc6 7.d4 Be7 8.dxc5 Bxc5 9.O-O a6 10.Na4 Be7 11.Nd4 Qc7 12.Nxc6 Qxc6 13.Nc3 O-O 14.Bd2
{After this somewhat cumbersome opening sequence, white finally finds itself ready to go. But black is better developed.}
14...Bd6 15.Rc1 Re8 16.Re1 Bd7 17.Kh1 Qb6 18.b3 Rac8 19.Kg1 h6 20.Rf1 g6 21.Kh1 Kg7 22.Qe1 Be5 23.Nd1 Ng4 24.Ba5 Qf6 25.f4 $2
{This move weakens the e3 pawn, which immediately becomes a target.}
25...exf3 26.Rxf3 Qg5 27.h4 Qh5 28.Bc3 Bxc3 29.Nxc3 Qe5 30.Rg3 Nxe3
{The goes the e3 pawn.}
31.Bd3 Rxc3 32.Rxe3 Qxe3 33.Qxc3+ d4 34.Qb2 Qf2 35.Rf1 Qxh4+
{Another pawn. Mychess is now two pawns up.}
36.Kg1 Re5 37.Qa3 Bb5 38.Bxb5 Rxb5 39.Qd6 Rf5 40.Rxf5 gxf5 41.Qe5+ Qf6 42.Qd5 b6 43.Kf2 Qh4+ 44.Kf3 Qg4+ 45.Kf2 Qf4+ 46.Qf3 Qd2+ 47.Qe2 Qf4+ 48.Qf3 Qxf3+ 49.Kxf3
{With the last pieces traded off, Mychess is entering an endgame with two pawns up.}
49...h5 50.a3 f6 51.Ke2 Kg6 52.Kd3 f4 53.Kxd4 Kf5 54.c4 h4 55.c5 bxc5+ 56.Kd3 f3 57.Ke3 fxg2 58.Kf2 g1=Q+ 59.Kxg1 h3 60.Kf2 Kg4 61.Kf1 Kg3 62.Kg1 h2+ 63.Kh1
{The white king is stuck, and Mychess wastes no time to go in for the kill.}
63...f5 64.a4 f4 65.b4 f3 66.bxc5 f2
{Ignoring the c pawn, which will not queen in time to make any problems.}
67.c6 f1=R#
{For good measure, underpromotes to a rook, mating.}
0-1

In the following example I play against the CP/M version. The computer makes no glaring blunders, but I am able to build up an attack on the kingside and sacrifice a rook to break through.

[White "BenRedic"]
[Black "Mychess 1.0 CP/M"]
[Result "1-0"]

1.e4 c5 2.Nf3 Nc6 3.Bb5 Nf6 4.Qe2 a6 5.Bxc6 dxc6 6.O-O e6 7.d3
{With the light square bishop off the board, I am putting my pawns on white squares and preparing to attack the weakened pawn structure on the queenside.}
7...Be7 8.Nc3 O-O 9.a4 Bd7 10.Be3 Qb6 11.b3 Qa5 12.Bd2 Qc7 13.Bg5 Qa5 14.Qe1 h6 15.Bd2 Qc7 16.a5
{Locking the queenside, possibly preparing a knight on b6.}
16...e5 17.h3
{Preventing Bg4.}
17...Be6 18.Na4 Nd7 19.Qc1
{Making no progress on the queenside, I turn my sights on the kingside. Planning Na4-c3-e2-g3, clearing away Nf3 and breaking with f4.}
19...Nf6 20.Nc3 h5 21.Ne2 Bd6 22.Ng3 g6 23.Ng5 Bd7 24.Ne2
{Strengthening f4 before the break.}
24...Rad8 25.Qb2
{Pinning e5.}
25...Rfe8 26.f4 Qc8 27.Rf3 Bc7 28.Bc3 Be6 29.Raf1 Nh7 30.Nxe6 Qxe6 31.f5 Qe7 32.Qc1
{Threatens to infiltrate with Qh6.}
32...g5 33.f6 Qf8 34.Rf5 c4 35.bxc4 Qc5+ $2
{Moves the queen away from the defense of the king. Surely mate is unavoidable now?}
36.Kh1 Bxa5 37.Bxa5
( 37.Rxg5+ {I was considering playing this sacrifice right away, but I was uncertain of the continuation after} 37...Kf8 38.Rxh5 Nxf6 {, so I decided to play it safe and just capture the bishop.} )
37...Qxa5 38.Rxg5+ Nxg5
( 38...Kf8 {would be a more stubborn defense, but the game is nevertheless over} 39.Rxh5 Nxf6 40.Qh6+ Ke7 41.Qxf6+ Kd7 42.Rxe5 )
39.Qxg5+ Kh7 40.Qg7# 1-0