White plays and wins - (3 x 5) x L. Prokes (Mate in charreteras)

Observando este mate de Prokes podemos preguntarnos: ¿que otros trebejos negros pueden hacer de topes o "charreteras" al rey negro exceptuando los peones? En a3 no puede estar un caballo porque daria jaque al rey blanco, no podría ser ni dama ni torre porque tomaria el peon que dá mate. La unica pieza negra que sirve de charreteras en a3 es un alfil. Veamos ahora que otra pieza podria estar en a5. Si fuera caballo nuevamente daria jaque y alfil no puede ser porque seria del mismo color que el alfil de a3 que es pieza obligatoria. Podria ser dama o torre negra la pieza apostada en a5. En resumen, con el rey negro en a4 las piezas negras deben ser alfil en a3 y dama o torre en a5.

Observing this Prokes mate, we might ask: what other black pieces can act as checks or "epaulettes" for the black king, except for pawns? A knight cannot be on a3 because it would check the white king; it cannot be a queen or a rook because it would capture the pawn, which gives mate. The only black piece that serves as an epaulette on a3 is a bishop. Let's now see what other piece could be on a5. If it were a knight, it would again check, and a bishop cannot be on a5 because it would be the same color as the bishop on a3, which is a mandatory piece. The black piece posted on a5 could be either a queen or a rook. In short, with the black king on a4, the black pieces must be either a bishop on a3 and a queen or a rook on a5.

¡¡¡Excelente!!! 💪