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
1.Sed3
Se5
2.Sd5
Rc4#
1.Sf3
Be5
2.Sd3
Sd6#
1.Kd4
Rxe5
2.Bd3
Bc5#
Szabo, Tibor
Magyar Sakkélet, 1983
8th HM
a) 1.Sb1+
Sc3
2.Kxc3
Bb2#
b) 1.Sg3+
Se4
2.Kxe4
Rf4#
Zalokocky, Roman
Gavriliv, Evgeny
Ulyanovskaya Pravda, 1984
1st Prize
1.Sd7
S7f6
2.Rxf6
Sg7#
1.Se8
S5f6
2.Bxf6
Sf8#
Semenenko, Oleksandr
Semenenko, Valery
I. Kavnatsky-100 MT, Problemist Ukrainy, 2011
1st Prize
a) 1.Rf7
Sf2
2.Qd7
Sg4
3.Sd6
e4+
4.Ke6
d5#
b) 1.Sf5
Sg3
2.Se3
Sf5
3.Sc4
e3
4.e6
Se7#
Niemann, John
Feenschach, 1963 (corr.)
2nd Prize
1.Sd5
Bb6
2.Sf4+
Sd5
3.Sg2+
Sef4#
Caillaud, Michel
Loustau, Jean-Marc
Rotenberg, Jacques
Rex Multiplex, 1983
2nd Prize
1.Re5
Bd5
2.Re6
Re5+
3.Qe4
Rf5#
Umnov move (white-white) x3