On the two squares where a white knight could check the black king, it would interfere with the line of guard of a white rook or bishop. Therefore in each two phases White moves the rook or bishop anti-critically, enabling the knight to mate on the critical square.
See also: Anti-critical move.
Alias: Brasil motif.
Abdurahmanović, Fadil
Magyar Sakkelet, 1979
1.Ba7
Bxh6
2.Rd4
Se3#
1.Rd1
Rxh6
2.Bd4
Sd6#