Tag description: Mating pattern in which the opponent king is confined to the edge of the board (usually the back rank) so can only defend by taking the checking piece or blocking. A back-rank mate may be delivered (1) by a rook or queen adjacent to the king, (2) by a smother from a knight or a pawn on the 7th rank, or (3) due to the opponent having no pieces with which to block. See http://zhchess.blogspot.com/2019/10/back-rank-mate.html
