Tamer Karatekin has composed a harder version of the Suli's Diamond endgame study.
For further historical background, diagrams, source discovery, and a video explanation of the solution,
see the dedicated Suli’s Diamond page on Shatranj.ai
and watch the associated documentary lecture
“Suli’s Diamond: The Most Mysterious and Challenging Chess Puzzle of All Time”
on YouTube.
Beware the rules in this article are the old form of chess (shatranj).
For these rules see: https://ancientchess.com/page/play-shatranj.htm
Because the PGN-tool at this website can't show you the moves, I give you the diagrams where a FEN is in the article:
Below the article with all the details:
See also: https://doi.org/10.5281/zenodo.19465731
Suli_Karatekin_Diamonds_Reverse_Ferz_40_positions
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