No. 54, Apr-Jun 2011
R0177 - Nikolai I. Beluhov
StrateGems, No. 54, Apr-Jun 2012
11+14. Release the position
[rRqnRbB1/1k1nQ1Pb/pppKppp1/4N3/3P4/2P2p2/1P1P4/8]
Solution
Retract: -1.a7xRb8R+ Sc5-d7 -2.Sd7-e5+ Sd3-c5 -3.Bf7-g8 Sb4-d3 -4.d3-d4 Sd5-b4 -5.e2xPd3 Sc7-d5 -6.Se5-d7 Bg8-h7 -7.Sc4-e5 (Not -7.c2-c3? Bh7-g8 -8.Bg8-f7 f4-f3 -9.Sf7-e5 f5-f4 -10.Sh8-f7 d4-d3 -11.Bf7-g8 Bg8-h7 -12.h7-h8S d5-d4 -13.h6-h7 h7xg6 and black is retro-stalemated) Bh7-g8 -8.Sa3-c4 Bg8-h7 -9.Sb5-a3 Sd5-c7 -10.Sc7-b5+ Bh7-g8 -11.Bg8-f7 Se3-d5 -12.Bf7-g8 Sg4-e3 -13.Bg8-f7 Se5-g4 -14.Bf7-g8 Sd7-e5 -15.Sd5-c7 Bg8-h7 -16.Se3-d5 Bh7-g8 -17.Sc4-e3 Bg8-h7 -18.Se5-c4 Bh7-g8 -19.Bg8-f7 f4-f3 -20.Sf7-e5 f5-f4 -21.Sh8-f7 d4-d3 -22.Bf7-g8 Bg8-h7 -23.h7-h8S d5-d4 -24.h6-h7 h7xSg6 -25.Se5-g6 Sc5-d7 -26.Sd7-e5+ and everything unlocks.
Five Knight-for-Knight substitutions along the same line of attack, four of them featuring the same pair of Knights! (A)
R0178 - Nikolai I. Beluhov
11+15. Last 36 single moves?
[2kNRKNq/P2npPrp/p1PP1pb1/2pRP1b1/P2p4/4p1n1/8/1r6]
Retracting e4-e5 too early is illegalized by the color effect, as the black pawns captured a white light-squared Bishop. -1…Sb6-d7+? leads to retro-stalemate, 24 retractions later. Retract: -1…Sb8-d7+ -2.a3-a4 Bh6-g5 -3.a2-a3 Bf4xPh6 -4.h5-h6 Sf5-g3 -5.h4-h5 Sh6-f5 -6.h3-h4 Bf5-g6 -7.h2-h3 Rg1-g7 -8.g7-g8S Sg8-h6+ -9.g6-g7 b2-b1R -10.g5-g6 b3-b2 -11.g4-g5 b4-b3 -12.g3-g4 b5-b4 -13.g2-g3 b7-b5 -14.b6xRa7 Ra8-a7 -15.b5-b6 a7-a6 -16.b4-b5 Sa6-b8 -17.b3-b4 Kb8-c8 -18.b2-b3 Bc8-f5 -19.Se6-d8.
The type and sequence of black's retractions at moves 4-7, can only be determined once the solver has realized that -18…Bc8-f5 must be unplayed 28 retractions later! (A)
R0179 - Nikolai I. Beluhov & Andrey Frolkin
12+15. Release the position
[bR1NkqQr/1NPrnRPp/2B1npp1/bpKp4/1p1p4/8/P4P1P/8]
Retract: -1...Sf4-e6 -2.Rc8-b8 Sg2-f4 -3.Rb8-c8 Sh4-g2 -4.Rc8-b8 Sf5-h4 -5.Rb8-c8 Sd6-f5 -6.Rc8-b8 Sf5-e7 -7.Rb8-c8 Sh4-f5 -8.Rc8-b8 Sg2-h4 -9.Rb8-c8 Se1-g2 -10.Rc8-b8 e2-e1S -11.Rb8-c8 e3-e2 -12.Rc8-b8 e4-e3 -13.Rb8-c8 e5-e4 -14.Rc8-b8 e7-e5! (the only way to resolve the retro-opposition) -15.Rb8-c8 Sc8-d6 -16.Se6-d8 Sd6/a7/b6-c8 -17.Sd8-b7+ and everything unlocks.
P0298 - Bernd Graefrath
Dedicated to Joerg Kuhlmann (60)
Corrected version (Nf3, instead of wNe2)
15+15. PG 6½ (Andernach)
[rnbq1rk1/pppp2pp/4pn2/5p1Q/8/4PN2/PPPP1PPP/RNB2RK1]
1.e3 f5 2.Bc4 Sf6 3.Bg8 Rxg8(=wR) 4.Rxf8(=bR) Kf7 5.Qh5+ Kg8 6.Sf3 e6 7.0-0. Castling and artificial castling. It may be hard to guess where the missing Bishops were captured! (A)
P0299 - Silvio Baier
12+12. PG 7½ 2 solutions
[2bqkbnr/1p1ppppp/8/8/8/8/P3PPPP/RN1QKBNR]
i) 1.d4 a5 2.d5 a4 3.d6 a3 4.dxc7 axb2 5.cxb8Q bxc1Q 6.Qxa8 Qxc2 7.Qa4 Qxd1+ 8.Qxd1.
ii) 1.d4 Sc6 2.Bf4 Sxd4 3.Bxc7 Qxc7 4.Qxd4 Qxc2 5.Qxa7 Qxb2 6.Qxa8 Qb6 7.Qa4 Qd8 8.Qd1.
The first solution shows the well-known combination of Pronkin(Q) and Ceriani-Frolkin(q) and the second, Rundlaufs of both Queens. (A)
P0300 - James Soliman
15+10. PG 12
[rnbq1b1k/pp6/5p1p/8/2B5/3PPK2/PBP2PPP/RN1Q2NR]
1.e3 c5 2.Ke2 c4 3.Kf3 c3 4.bxc3 d5 5.Bb2 d4 6.cxd4 e5 7.dxe5 Sf6 8.exf6 h6 9.fxg7 f6 10.gxh8R Kf7 11.Bc4+ Kg7 12.d3 Kxh8.
The white pawn b2 captures its way to h8, promoting to a Schnoebelen Rook.
P0301 - Guy Sobrecases
16+14. PG 12½
[rnbqkb1r/Pppppppp/Q7/1K6/4P2R/8/1PPP1PPP/1NB2BNR]
1.a4 Sf6 2.a5 Sd5 3.Ra4 Sb6 4.axb6 a5 5.Rh4 a4 6.e4 a3 7.Qe2 a2 8.Qa6 a1S 9.Ke2 Sb3 10.Kd3 Sd4 11.Kc4 Sdc6 12.Kb5 Sa7+ 13.bxa7.
A 9-move tempo maneuver, showing the bPa7 Excelsior, promotion into a bS Phoenix, and long switchback for a sacrifice on a7. (A)
P0302 - Silvio Baier
13+14. PG 18
[5k2/4p2p/n2brn1r/p2p1pp1/6b1/7q/2P1PPPP/RNBQKBNR]
1.d4 g5 2.d5 Bg7 3.d6 Kf8 4.dxc7 d5 5.a4 Qd7 6.a5 Qh3 7.a6 Bg4 8.axb7 a5 9.c8B Ra6 10.Be6 Rxe6 11.b4 Sa6 12.b8B f5 13.Be5 Bxe5 14.b5 Sf6 15.b6 Rg8 16.b7 Rg6 17.b8B Rh6 18.Bd6 Bxd6.
Three Ceriani-Frolkin Bishops captured by pieces, combined with a white home-base. See also P1007296 in PDB: http://www.softdecc.com/pdb/index.pdb (A)
P0303 - James Soliman
Correct stipulation: PG18 instead of PG21
15+12. PG 18
[Bn2kbn1/p1pp1p2/3Qp2p/3N1RPR/K1P2B1r/2P1P2N/PP4P1/5b2]
1.d4 Sc6 2.Sd2 Sxd4 3.Sb3 Sxe2 4.Kd2 Sxg1 5.Bd3 e6 6.Bxh7 Ba3 7.Bd3 Rxh2 8.bxa3 Rxg2 9.Rh7 g6 10.Rxf7 Sh6 11.Rxd7 Sf5 12.Rd4 Qd6 13.a4 Kd7 14.Ba3 (N) Kc6 15.Qb1 Kb6 16.Sc1+ Ka5 17.Rb4 Qh2 18.c4 (D) Rxf2+. The white pieces form an N (for Nicolas) after white’s 14th move, which in the course of play transforms into a D (for Dupont). (A)
P0304 - Roberto Osorio & Jorge J. Lois
14+12. PG 24
[rnbqkbnr/p1p1p2Q/4B3/p4PR1/6R1/PPP1P1B1/2NN3P/7K]
1.a4 f5 2.a5 f4 3.Ra4 f3 4.Sa3 fxg2 5.f4 g5 6.Sf3 g1B 7.Bh3 Bd4 8.Be6 Bc3 9.dxc3 g4 10.Qd3 g3 11.Qxh7 g2 12.f5 g1B 13.Bf4 Bc5 14.e3 d5 15.0-0 d4 16.Kh1 d3 17.Rg1 d2 18.Rg5 d1B 19.Bg3 Be2 20.Rag4 Bc4 21.Sd2 Bb3 22.cxb3 b6 23.Sc2 Ba3 24.bxa3 bxa5.
An Impostor Pawn (IP) is a Pawn not originally from the line where it stands, provided that: a) the impostor feature is legal by retroanalysis (i.e. it could legally be the original pawn of this line) and b) the original pawn no longer stands on this line. We are showing a triplication of the feature produced by three Ceriani-Frolkin Bishops. (A)
P0305 - Unto Heinonen
14+15. PG 25½
[1qb3n1/r1p3rp/p1nkP3/1pp1p2p/1b6/N3P3/PPP4P/RQBK1BNR]
1.d4 e5 2.Bh6 gxh6 3.g4 h5 4.Bg2 Sh6 5.Bc6 dxc6 6.Sa3 Be6 7.Qb1 Bb4+ 8.Kd1 c5 9.f4 Sc6 10.f5 Qb8 11.fxe6 f5 12.d5 f4 13.d6 f3 14.d7+ Ke7 15.d8B+ Kd6 16.Bg5 f2 17.Bc1 f1B 18.e3 Ba6 19.g5 b5 20.g6 Bc8 21.g7 a6 22.g8B Ra7 23.Bf7 Rg8 24.Bg6 Rg7 25.Bd3 Sg8 26.Bf1.
P0306 - Jorge J. Lois & Roberto Osorio
13+12. PG 26
[rn1qk2r/Bpppppp1/7Q/8/4P1P1/2P1K3/1P1P2BP/1Nn3NR]
1.c3 h5 2.Qa4 Rh6 3.Qxa7 Ra6 4.a4 Sc6 5.Qb8 Sf6 6.Qxc8 Sd5 7.Qb8 Sdb4 8.Qa7 Qb8 9.Qe3 Qa7 10.Qh6 0-0-0 11.Qh8 Qb8 12.Qxf8 Ra8 13.Qh8 Sa6 14.Qh6 Rh8 15.a5 Kd8 16.Ra4 Ke8 17.Rg4 hxg4 18.e4 g3 19.Ke2 gxf2 20.g4 Qd8 21.Bg2 Sab8 22.a6 f1S 23.a7 Sg3+ 24.Ke3 Se2 25.axb8B Sxc1 26.Ba7 Sb8.
Triple sibling (bS, bR, bR), triple Circuit from and to home-square (bS, bQ, bK), double Prenix (=anticipatory Phoenix) (bS and wB), ending in a diagram with a visible promoted man (wBa7), but no extra-set material. (A)
