Problem Display
PID: 242616 (3R4/2nB4/6p1/2p5/K2p1Q2/2NkN1n1/8/4B3 w - - 0 1)

Casa, Alex

Source?, 0000

3R4/2nB4/6p1/2p5/K2p1Q2/2NkN1n1/8/4B3

#2

7 + 6


15148 Sadier Collection 2021
5454 Near Snap 2022

SOLUTION


  • SOUND
  • Sets
    • 1...Sf1
      • 2.Qe4#
    • 1...Sh1
      • 2.Qe4#
    • 1...Se2
      • 2.Qe4#
    • 1...Se4
      • 2.Qxe4#
    • 1...Sf5
      • 2.Qe4#
    • 1...Sh5
      • 2.Qe4#
    • 1...dxc3
      • 2.Bb5#
    • 1...dxe3
      • 2.Bf5#
  • Tries
    • 1.Bb5+?
      • 1...c4
        • 2.Bxc4#
        • 2.Rxd4#
        • 2.Qxd4#
      • 1...Sxb5!
    • 1.Bf5+?
      • 1...Se4
        • 2.Bxe4#
        • 2.Qxe4#
      • 1...Sxf5
        • 2.Qe4#
      • 1...gxf5!
  • Keys
    • 1.Qf2!
      • threat
        • 2.Qd2#
      • 1...dxc3
        • 2.Bf5#
      • 1...dxe3
        • 2.Bb5#
      • 1...Sf1
        • 2.Qe2#
      • 1...Se2
        • 2.Qxe2#
      • 1...Se4
        • 2.Qe2#

This anticipates 261278(1982)

FEATURES


  • Static
    • TYPE = THREAT
    • CHANGED MATES = 5
    • ADDED MATES = 0
    • REMOVED MATES = 3
  • Sets
    • S(b);N_GUARD::QAB1(E)
    • S(b);N_GUARD::QAB1(E),XS(b)
    • P(c);XS(B)::R(G)+B(F),DCHECK
    • P(c);XS(C)::R(G)+B(F),DCHECK
  • Tries
    • Try
      • B(F);CHECK,P_PINP(c)
      • Refutation
        • S(f);XB(F)
    • Try
      • B(F);CHECK,P_PINP(c)
      • Vars
        • S(b);N_GUARD,XB(F)::QAB1(E)
      • Refutation
        • P(e);XB(F)
  • Actual
    • Q(E);
    • Threat
      • QAR1(E)
    • Vars
      • P(c);XS(B)::R(G)+B(F),DCHECK
      • P(c);XS(C)::R(G)+B(F),DCHECK
      • S(b);N_GUARD::QAB1(E)
      • S(b);N_GUARD::QAB1(E),XS(b)


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).