No.1718 (JC&BM)

Shadow-chess
 1. There is an illegal (shadow) puppet in the chess problem.
2. A piece is illegal if it stands in an inaccessible field, or the
   author stigmatizes
   a piece and classifies it as illegal (stigma on it).
3. A solution involving an illegal piece is not allowed.
   The solution containing the illegal piece is a shadow
   solution.
4. If the x legal piece on a) legal square is replaced by the y
   illegal piece on b)
   illegal square, the y illegal piece on a) legal square will
   remain illegal, and b)
   will be illegalx legal piece placed on square remains legal.
5. A piece becomes illegal if the square on which it stands
   becomes inaccessible
   due to a change in the home position.
 See A), B) and C) chessproblems!

 A)
János Csák & Béla Majoros
Hungary
 Christmas card, 2021
Cureirul Problemistic, 2021
 b6b/1p4Pq/8/1p1PP1K1/2P1kP2/1n2p3/4P3/8
 h#2 (7+8)
b) bPb7<–>wPg7
a)
The black Bishop on the a8 is a illegal piece, so the
1. b6 g8Q 2. Bxd5 Qxd5 # solution is also (shadow)
illegal, and the solution is:
1. Sd4 g8S 2. Bf6 + Sxf6 #
b)
Now the black Bishop on the h8 makes the
1. g6 b8Q 2. Bxe5 Qxe5 # line a shadow (illegal),
so the solution is:
1. Qg8 bxa8Q 2. Qxd5 Qxd5 #

B)
János Csák & Béla Majoros
Hungary
 
Julia’s Fairies, 2022
25.01.2022 No. 1684
version     of No.1684 – 28.02.2022
 6bb/P4Pp1/8/7K/5p2/3pk1P1/3p2P1/8
 h#2 (5+7)
b) bBg8<–>bBh8
a)
Because h8bB is a shadow-piece (illegal-piece),
there can be no solution (shadow-solution):
1.g5 a8=Q 2.Bd4 Qf3# shadow
The g8 bB is legal-piece, so the solution is:
1.Ke4 f8=Q 2.Bd5 Qxf4#
b)
Because g8bB shadow-piece (illegal-piece)
after exchange, there can be no solution (shadow-solution):
1.Ke4 f8=Q 2.Bd5 Qxf4# shadow
The h8 bB is legal-piece, so the solution is:
1.g5 a8=Q 2.Bd4 Qf3#
C)
János Csák & Béla Majoros
Hungary
 Julia’s Fairies, 2022
29.06.2022 No. 1718
3bb3/2Pp3P/8/8/N1k5/1p6/4K3/8
  h#2 (4+5)
e8bB illegal piece! (stigma)
b) bBe8<–>bBd8
a)
Because e8bB is a shadow-piece (illegal-piece),
there can be no solution (shadow-solution):
1.d5 h8=Q 2.Bb5 Qc3#
The d8bB is legal-piece, so the solutions is:
1.Be7 c8=Q+ 2.Bc5 Qxc5#
1.Kb5 cxd8=Q 2.Ka6 Qb6#
b)
Because c8bB shadow-piece (illegal-piece)
after exchange, there can be no solutions (shadow-solutions):
1.Be7 c8=Q+ 2.Bc5 Qxc5#
1.Kb5 cxd8=Q 2.Ka6 Qb6#
The e8bB is legal-piece, so the solutions is:
1.d5 h8=Q 2.Bb5 Qc3#