Now for an application on the kingside. White’s bishop on b3 seals off f7 and g8, and White has a battery of queen and rook aimed at e8. Yet he can’t quite mate with these forces because Black protects e8 three times. The solution is to involve White's least conspicuous piece: the bishop on d2, which can reach h6 in one step. White just needs to clear the diagonal from h6 to the Black king’s square, and this he can do with his queen by playing the familiar QxN+. Black is forced to reply g7xQ (the king still has no flight squares). Now Bh6 mates. Normally in Boden’s mate the two bishops are able to apply unbearable pressure against the king because the king is prevented from retreating by a wall of its own pieces. Here the “wall” is created by the rook on e1, which keeps the king east of the e-file.