Umnov move
In a helpmate, a piece of either colour moves to a square vacated by another piece of either colour.
See also: FML; Umnov mate; Closed chain of Umnov; Consecutive Umnov; Delayed Umnov.
Zappas, Byron
Probleemblad, 1999
Prize
h#2 3.1... (5+8)
1.Sed3
Se5
2.Sd5
Rc4#
1.Sf3
Be5
2.Sd3
Sd6#
1.Kd4
Rxe5
2.Bd3
Bc5#
In two solutions Black-White Umnov move (in W1), in all solutions White-White (on W2).
Niemann, John
Feenschach, 1963 (corr.)
2nd Prize
h#3 (5+8)
1.Sd5
Bb6
2.Sf4+
Sd5
3.Sg2+
Sef4#
All white moves are Black-White Umnov moves.
Caillaud, Michel
Loustau, Jean-Marc
Rotenberg, Jacques
Rex Multiplex, 1983
2nd Prize
h#3 (3+15)
1.Re5
Bd5
2.Re6
Re5+
3.Qe4
Rf5#
All moves starting from W1 are Umnov moves.