In a helpmate in three (or more) moves, in the first phase, some piece visits in succession three squares. In another phase, anothe piece of the same color (or the same piece) visits the same three squares also in succession, but in opposite order.
In a helpmate in two moves, reduced form of the theme is allowed: in one phase some piece plays to square A, and then to square B. In another phase, another piece of the same color plays to square B, and then to square A.
Zalokocky, Roman
Suvorovskij Natisk, 1965
a) 1.Kb5
Qe1
2.Ka4
Qb4#
b) 1.Kf2
Bb4
2.Re3
Be1#
Abrosimov, Viktor
13th Russian Team Championship, 1999
3rd Place
1.Bh5
Sf6
2.Bxg4
Se4
3.Bf3
Sec3#
1.Kf3
Sc3
2.Kxg4
Se4
3.Kh5
Sef6#
Cinko, Peter
feenschach, 1988
a) 1.Sc3
bxc3
2.Rg7
cxd4
3.Be5
dxe5
4.Qf6
exf6
5.Re7
fxg7#
b) 1.Rc3
Kg7
2.Qa4
Kf6
3.Ba5
Ke5
4.Sa3
Kxd4
5.Bb5
bxc3#
Lundström, Anders
British Chess Magazine, 1978
1.Kb5
Rh8
2.Ka4
Rh1
3.Bb5
Ra1#
1.Kc7
Ra1
2.Kd8
Rh1
3.Ke8
Rh8#
Pandar, Okan
Problemist of Ukraine, 2020
1.Ke4
Rc6
2.R4d5+
Rc5
3.Kd4
Rc4#
1.Kxe6
c4
2.Kd7
c5
3.Se6
c6#