Grasshopper(G): Moves along Q-lines over another unit of either color to the square immediately beyond that unit. A capture maybe made on arrival, but the hurdle is not affected.
No.1351Dmitrij Baibikov Israel original – 16.12.2018
white Bf2h5 Gg2 Kg5 Qh3 Pe2d2c2b3e4h6f7 Sg1g6 Rf3f4
black Be1 Gg4 Kf1 Qg3 Pe3f5c6h7g7d7 Sh1 Rh2h4
Last 20 single moves? (13+11) C-
Promotion in Grasshopper allowed
{
} 1...h7*g6 2.h6-h7 c6-c5 3.h7-h8=G c5-c4 4.Gh8-f6 c4-c3 5.Gf6-b2 c3*b2 6.b3-b4 b2-b1=G {
} 7.b4-b5 Gb1-d3 8.e2*d3 Gg4-e2+ 9.Gg2-g4+ Ge2-g2 10.d3-d4 f5*g4 11.Qh3*g2+ {
The solution given by author, 20 moves back starting from the last move:
Retro: (Phase I) 1.Qh3xGg2+ f5xGg4 2.d3-d4 Ge2-g2 3.Gg2-g4+
Gg4-e2+ 4.e2xGd3 (Phase II) 4...Gb1-d3 5.b4-b5 b2-b1=G 6.b3-b4
c3xGb2 (Phase III) 7.Gf6-b2 c4-c3 8.Gh8-f6 c5-c4 9.h7-h8=G c6-c5!
10.h6-h7 h7xSg6 and further, for example, 11.Se7-g6 c7-c6 12.g6xSf7
S~-f7 13.S~-e7 f7-f5 etc.(C-)}
Bicolor grasshopper quartex (GGgg), 2-units tempomaneuver (Gg), phases transformation (3 phases), exact retroplay (20 single moves).
Note: disappearing of 3 or more Grasshoppers was released early twice: in classical Retro (Nikita Plaksin, PDB/P0002907) and in Proof Games (Michel Caillaud, PDB/P1240680). (Author)
Excellent!