Circe Equipollents: After a piece is captured, it is immediately replaced on the square which is the same distance and direction from the square of its capture, as was that square from the square upon which its captor commenced its move. (If Qf7 captures a Pawn on e7, it is reborn on d7, because d7 is a same distance and direction from e7 as e7 is from f7. Similarly, if Qg7 captures a piece on ‘e7’ its rebirth square is ‘c7’). If the rebirth square is occupied the captured piece disappears. Castling with replaced Rook is permitted. Pawns may be reborn on the 1st and 8th ranks. Pawns reborn on the 8th rank are promoted as part of rebirth and the promotion is chosen by the player who makes the capture, i.e., if White captures a black Pawn, and the black Pawn is reborn on the 8th rank, White (not Black) decides what Black’s Pawn will be promoted to. Pawns reborn on the 1st or 8th rank can make only one-square move (for example black Pc8 can play only on c7 or it can capture an enemy units on ‘b7’ or ‘d7’). During the en passant capture, the Pawn is replaced on the rank opposite of the captor. For example, if Black moves c7-c5, White Pawn on ‘b5’ captures en passant, moves to ‘c6’, while the black Pawn is reborn on ‘d6’.
No.1520Chris Feather England original – 30.06.2020
Inspired by Hans Peter Rehm's remarkable book on logic in fairy chess (Logik & Zweckreinheit im Märchenscach, Fee=Nix 2017) I have tried to compose serieshelpmates with a strong logical element, although of course they cannot exactly meet the criteria of the German logical school of composition. Thus in the present problem the final position is obvious but in order to find (or simply to understand) the solution, it is necessary to see why the Sa7 must be moved to a5 and why it is too soon to start with a capture on d8 or f8. (Author)