The puzzle is offered in two variations: full (1) and abbreviated (2).
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Is it attainable to place a cooperative checkmate right here in three strikes? (white makes the primary transfer)
h#2,5 (AP) Stepan Nichto. chessok.web, 07.05.2025
White begins and works along with black to checkmate black in three strikes. You have to a posteriori proof of the legality of e.p., which is marked within the task with the abbreviation AP.
If utilizing AP appears tough to you, then the duty will be solved as a easy retro puzzle with out subsequent direct play.
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What was the final transfer within the sport whether it is identified that each white and black retained the fitting to castling?
Generally, fixing puzzle 2 is a obligatory a part of fixing puzzle 1.
IMPORTANT: The extra situation of Puzzle 2 doesn’t apply in Puzzle 1. That’s, in puzzle 1, we shouldn’t have any further details about whether or not the events have the fitting to castling or not. That’s, when fixing puzzle 1, the usual castling guidelines and e.p. Plus the AP conference are used.
(16.1) Castling conference. Castling is permitted until it may be
proved that it isn’t permissible.(16.2) En-passant conference. An en-passant seize on the primary
transfer is permitted provided that it may be proved that the final transfer was the
double step of the pawn which is to be captured [15].[15] AP conference (in accordance with the Piran Codex of 1958).
The proof wants not be given solely by retpoanalysis, the “e.p.” seize
may also be legalised in a while within the additional sourse of the answer.
