Themes and patterns

A compositional checkmate combining purity around the mated king with economical participation by the mating side's pieces.

A composition theme where two same-colored pieces mutually block one another by occupying the same intersection square in separate variations.

A composition theme where a White piece occupies the intersection of two Black defensive lines and forces interference between them.

A theme in which a sacrifice at two crossing defensive lines makes either capturing piece obstruct the other.

A theme in which one piece moves ahead along a row, column, or diagonal so a same-color piece can follow on that line.

A mechanism in which two Black pieces screen their king on one line and either one's departure prevents the other from moving away.

A theme in which a pawn starts on its original row, crosses the board, and promotes, meaning it becomes another piece.

A composition theme in which every Black promotion is answered by a White promotion to the same piece.

A theme in which several continuations appear possible, but after each defense exactly one works and the others are excluded.

A theme in which the same Black defenses receive White mating replies that rotate cyclically between two or more parts of the solution.

A theme in which the same two or more Black defenses receive different White mates across at least three phases of a problem.