Pillsbury’s Mate is a variation of Morphy’s Mate. This checkmate pattern is done with a Rook and a Bishop as well, only the checkmate is done with a Rook instead of a Bishop.
This mate is usually achieved by sacrificing material for a better position with a Bishop and Rook. Removing the pawn in front of the King after castling is common. Once they are on the right squares, a beautiful checkmate can end the game.
In this example, Black is checkmated with a Rook. The dark squared Bishop prevents Black from escaping.
Black has a Queen and White is in serious danger. However, White has given up material in order to gain this position to win the game. Even though Black has a big material advantage, White wins with this next move.
White moves Rg1 to deliver checkmate. Whites dark squared Bishop prevents Black’s King from h8.