Matching strategy involving Zilahi (captures of bishop / rook while rook / bishop mate) and
Grimshaw (mutual interferences of the rook and bishop at e4).
This one was used in the World Solving Championship of 2000 and found very difficult!
Again, interchange of function between White and Black as first the bishop then the rook
go beyond d2.
(H)
2nd Prize, Orbit, 2001/II
Helpmate in 3 (b) wPe3->f2
a) 1.Qa5 f5 2.Kb6 Rxb4 3.Rxe3+ Bxe3
b) 1.Rxb5 f3+ 2.Kb4 Bxb6 3.Bxf4 Rxf4
Reciprocally changed functions of the queen and b4 rook, and b3 rook and c7 bishop.
(I)
Sachova Skladba, 2003
Helpmate in 3 (b) d3 = black pawn
a) 1.Sd6 Rb7 2.Kd4 Rb4+ 3.Kc5 d4
b) 1.Sc5 Bb7 2.Kc4 Rxe4+ 3.Kb5 Rb4
No classic, but I have a soft spot for this quirky one. “Follow-my-leader”
effects at b7, and different routes of the rook to b4. Difficult to solve, I should think!
(J)
Schach-Aktiv, 2003
Helpmate in 3 (b) remove bPe5
a) 1.Sxc3 Rf4 2.Qe4 fxe4 3.Kd4 Sf5
b) 1.gxf3 Se6 2.Bd4 cxd4 3.Ke4 Re5
Reciprocally changed roles for the white pawns, and for the rook and knight, which open
lines for the queen and bishop.