MESON Chess Problem Database
Problem Display
PID: 12045 (b2N4/2P3QP/3p1B1p/R1rr1k2/4n1pK/5qpP/4Nn2/1B3R2 w - - 0 1)
Keller, Michael
Prahl, Gerd
Die Schwalbe, 1974
#2
11 + 11
SOLUTION
- SOUND
- Sets
- 1...Qg2
- 2.hxg4#
- 1...Qa3
- 2.hxg4#
- 1...Qb3
- 2.hxg4#
- 1...Qc3
- 2.hxg4#
- 1...Qd3
- 2.hxg4#
- 1...Qe3
- 2.hxg4#
- 1...Rxa5
- 2.c8Q#
- 2.c8B#
- 1...Rb5
- 2.c8Q#
- 2.c8B#
- 1...Rc6
- 2.Rxd5#
- 1...Rd1
- 2.c8Q#
- 2.c8B#
- 1...Rd2
- 2.c8Q#
- 2.c8B#
- 1...Rd3
- 2.c8Q#
- 2.c8B#
- 1...Rd4
- 2.c8Q#
- 2.c8B#
- 1...Sd1
- 2.hxg4#
- 1...Sh1
- 2.hxg4#
- 1...Sd3
- 2.hxg4#
- 1...h5
- 2.Qg5#
- 1...Qg2
- Tries
- 1.Bc3?
- threat
- 2.Qf6#
- 2.Qf7#
- 1...Qxc3
- 2.hxg4#
- 1...Rxc7
- 2.Qf6#
- 1...Qd3
- 2.Qxg4#
- 2.hxg4#
- 1...Rd3
- 2.c8Q#
- 2.c8B#
- 1...Rd4
- 2.c8Q#
- 2.c8B#
- 1...Re5
- 2.Qf7#
- 1...Sd3
- 2.Qxg4#
- 2.hxg4#
- 1...Rxc3!
- threat
- 1.Bd4?
- threat
- 2.Qf6#
- 2.Qf7#
- 1...Rxc7
- 2.Qf6#
- 1...Rxd4
- 2.c8Q#
- 2.c8B#
- 1...Qd3
- 2.Qxg4#
- 2.hxg4#
- 1...Re5
- 2.Qf7#
- 1...Sd3
- 2.Qxg4#
- 2.hxg4#
- 1...Rc2!
- threat
- 1.Be7?
- threat
- 2.Qf6#
- 1...Qc3
- 2.hxg4#
- 1...Qd3
- 2.hxg4#
- 1...Rd3
- 2.c8Q#
- 2.c8B#
- 1...Sd3
- 2.hxg4#
- 1...Rc2!
- threat
- 1.Rxf2?
- threat
- 2.hxg4#
- 1...gxh3
- 2.Rxf3#
- 1...h5
- 2.Qg5#
- 1...gxf2!
- threat
- 1.Qxh6?
- threat
- 2.Qg5#
- 1...Sxh3
- 2.Sxg3#
- 1...Rc2
- 2.Sd4#
- 1...Qd3
- 2.hxg4#
- 1...Qe3
- 2.hxg4#
- 1...Rd3
- 2.c8Q#
- 2.c8B#
- 1...Sd3
- 2.hxg4#
- 1...Qf4!
- threat
- 1.hxg4+?
- 1...Sxg4
- 2.Rxf3#
- 1...Qxg4+!
- 1...Sxg4
- 1.h8Q?
- threat
- 2.Qgh7#
- 2.Qhh7#
- 1...Rxc7
- 2.Qhh7#
- 1...Qxe2!
- threat
- 1.Bc3?
- Keys
- 1.Bg5!
- threat
- 2.Qf6#
- 1...hxg5+
- 2.Qxg5#
- 1...Rc2
- 2.Sd4#
- 1...Qc3
- 2.hxg4#
- 1...Qd3
- 2.hxg4#
- 1...Rd3
- 2.c8Q#
- 2.c8B#
- 1...Sd3
- 2.hxg4#
- threat
- 1.Bg5!
FEATURES
- Static
- TYPE = THREAT
- CHANGED MATES = 0
- ADDED MATES = 2
- REMOVED MATES = 8
- Sets
- Q(b);N_GUARD,N_SPINS(d),P_SPINS(a)::P(D),XP(e)
- R(f);N_GUARD,XR(F)::P=Q
- R(f);N_GUARD::P=Q
- R(f);OGATE,P_SPINR(g)::R(F),XR(g)
- R(g);P_SPINR(f)::P=Q
- R(g);N_SPINS(d),P_SPINR(f)::P=Q
- S(a);N_GUARD,P_SPINQ(b)::P(D),XP(e)
- S(a);N_GUARD,N_SPINS(d),P_SPINQ(b)::P(D),XP(e)
- P(j);N_GUARD::QAR1(I)
- Tries
- Try
- B(G);
- Threat
- DUALS(2)
- Vars
- Q(b);N_GUARD,N_SPINS(d),P_SPINS(a),XB(G)::P(D),XP(e)
- R(f);P_SPINR(g),XP(H)::QAR1(I)
- R(g);N_SPINS(d),P_SPINR(f)::P=Q
- R(g);P_SPINR(f)::P=Q
- R(g);::QAR2(I)
- Refutation
- R(f);P_SPINR(g),XB(G)
- Try
- B(G);
- Threat
- DUALS(2)
- Vars
- R(f);P_SPINR(g),XP(H)::QAR1(I)
- R(g);P_SPINR(f),XB(G)::P=Q
- R(g);::QAR2(I)
- Refutation
- R(f);N_SPINS(d),P_SPINR(g)
- Try
- B(G);
- Threat
- QAR1(I)
- Vars
- Q(b);N_GUARD,N_SPINS(d),P_SPINS(a)::P(D),XP(e)
- R(g);N_SPINS(d),P_SPINR(f)::P=Q
- S(a);N_GUARD,N_SPINS(d),P_SPINQ(b)::P(D),XP(e)
- Refutation
- R(f);N_SPINS(d),P_SPINR(g)
- Try
- R(B);P_PINQ(b),XS(a)
- Threat
- P(D),XP(e)
- Vars
- P(e);N_GUARD,XP(D)::R(B),XQ(b)
- P(j);N_GUARD::QAR1(I)
- Refutation
- P(c);N_SPINQ(b),XR(B)
- Try
- Q(I);XP(j)
- Threat
- QAR1(I)
- Vars
- S(a);P_SPINQ(b),XP(D)::S(C),XP(c)
- R(f);N_SPINS(d),P_SPINR(g)::S(C)
- Q(b);N_GUARD,N_SPINS(d),P_SPINS(a)::P(D),XP(e)
- R(g);N_SPINS(d),P_SPINR(f)::P=Q
- S(a);N_GUARD,N_SPINS(d),P_SPINQ(b)::P(D),XP(e)
- Refutation
- Q(b);
- Try
- P(D);CHECK,XP(e)
- Vars
- S(a);OGATE,P_SPINQ(b),XP(D)::R(B),XQ(b)
- Refutation
- Q(b);CHECK,N_SPINS(d),P_SPINS(a),XP(D)
- Try
- P(J);
- Threat
- DUALS(2)
- Vars
- R(f);P_SPINR(g),XP(H)::QAB(J)
- Refutation
- Q(b);N_SPINS(d),P_SPINS(a),XS(C)
- Try
- Actual
- B(G);
- Threat
- QAR1(I)
- Vars
- P(j);CHECK,OGATE,XB(G)::QAR1(I),XP(j)
- R(f);N_SPINS(d),P_SPINR(g)::S(C)
- Q(b);N_GUARD,N_SPINS(d),P_SPINS(a)::P(D),XP(e)
- R(g);N_SPINS(d),P_SPINR(f)::P=Q
- S(a);N_GUARD,N_SPINS(d),P_SPINQ(b)::P(D),XP(e)
Developed and maintained by Brian Stephenson.
Implemented with HTML5, MySQL, Perl (with, inter alia, CGI::Simple, HTML::Template & XML::LibXML) &
CSS/Javascript (jQuery, Bootstrap & DataTables).