Swordfish 14.4, Blue Marlin 14.4

[dorsz]

At the beginning I would like to point out that Swordfish and Blue Marlin are not stronger than Stockfish. If you are looking for more Elo you may not be interested. The purpose of these engines is to provide interesting and effective chess games. Swordfish and Blue Marlin are engines based on Stockfish and ideas used in Bluefish by Eelco de Groot.

Swordfish has a reasonable balance between strength and tactical abilities. It still has solid style of playing and achieves good results in test suites. It can be useful for analyzing sharp positions where regular Stockfish can overlook some tactics.

Blue Marlin is more focused on king attack and sacrifices. It provides very sharp and attractive games.

The new engines, compared to the 14.3 version, should be slightly stronger and better tactically.

14.4 vs 14.3:
https://www.mediafire.com/view/lck2tsww ... 3.png/file#
Tactics:
https://www.mediafire.com/view/dn8c7eoh ... s.png/file#

[dorsz]

Each archive contains both engines:
x64 AVX2 - https://www.mediafire.com/file/7tkw8gyg ... 2.zip/file
x64 BMI2 - https://www.mediafire.com/file/odmq90uk ... 2.zip/file
x64 modern - https://www.mediafire.com/file/pagop2il ... n.zip/file
x64 base - https://www.mediafire.com/file/4frggbit ... e.zip/file
sources - https://www.mediafire.com/file/2u5r06t8 ... s.zip/file

[dorsz]

I have never before match my engines against Stockfish because strength was not so important to me. However, out of curiosity, I started yesterday a tournament between Swordfish 14.4, Blue Marlin 14.4, Stockfish 14.1 (my latest engines are based on very close version to it) and Stockfish 14 to estimate their strength. The obvious favorite for me, Stockfish 14.1, finished a place behind Swordfish 14.4. It is interesting and surprising, especially because of how different some values are in Swordfish 14.4 comparing to Stockfish and how often it chooses to play a different lines.

I attach the result of the tournament (1m + 1s, 4 cores 3600MHz, opening book with colors reversed) and additionally updated tactics table with Stockfish 14.1 and Stockfish 14.

Tournament result:
https://www.mediafire.com/view/oen1pzdn ... 4.png/file#
Tactics (updated):
https://www.mediafire.com/view/ua2yk3ez ... s.png/file#

[sarona]

Thanks again for making these (updated) engines available.

Blue Marlin is becoming one of my favorites.

[dorsz]

I found a serious bug in Blue Marlin 14.4. Sometimes it could resign in winning position. It turned out that the problem was already in version 14.3. It is fixed in build 14.4a. Swordfish 14.4 does not need any corrections.

Previous links are deleted. Below are links to Swordfish 14.4 (unchanged) and Blue Marlin 14.4a (fixed).
Each archive contains both engines:
x64 AVX2 - https://www.mediafire.com/file/fp3tvy14 ... 2.zip/file
x64 BMI2 - https://www.mediafire.com/file/7cmqm6yd ... 2.zip/file
x64 modern - https://www.mediafire.com/file/9g60h8hs ... n.zip/file
x64 base - https://www.mediafire.com/file/61v40cfc ... e.zip/file
sources - https://www.mediafire.com/file/n3vyf8co ... s.zip/file

[sarona]

Thanks for pointing that bug out.

Now downloading the AVX2 Blue Marlin 14.4a binary.

[dorsz]

Thanks Sarona for correcting some of the untrue things in other chess forums (talkchess, chess2u etc.) about these engines. Unfortunately things like these are unavoidable. For example now one famous troll on talkchess called Guenther starts criticizing again "discovering" some settings inspired by Eelco. It is exactly what I describe and the purpose of these modifications of these engines at the beginning of every topic where I release my engines.

[sarona]

I wanted to set the record straight on who was the actual creator of these derivatives. Blue Marlin and Swordfish are the products of your time and effort. No way anybody should ethically cut and paste your words here and create a new thread in another forum and then conveniently leave out your name as the author.

Suggesting that your engines were not GPLv3 compliant on Talkchess prompted me to mention your thread here at OpenChess.



I agree with Alex concerning Blue Marlin (and also Swordfish). I hope that this shoddy treatment does not discourage you from further updates and future contributions to the computer chess community.

Regards from Canada,
Ron