Illegal position

The position cannot be achieved by a legal sequence of moves from the game array. Illegal positions are not acceptable for composition tournaments unless the tournament conditions so stipulate.

See also: Promoted force.

Pfeiffer, Gerhard

Die Schwalbe, 1985

Spec. HM

h#9 (2+15)

1.d1=Q Kg1 2.Qd5 Kh1 3.Qf3 gxf3 4.a1=Q f4 5.Qa2 f5 6.Qe6 fxe6 7.c1=Q e7 8.Qc5 e8=S 9.Qa7 Sc7#

Illegal position: 10 black pawns.

View in Helpmate Analyzer

FEN: kn6/1n6/2pp4/8/p7/4p1p1/ppppp1P1/1r2b2K

External links:

PDB: P0500863

Hilmar, Ebert

Jugendschach, 1981

h#3.5 (2+9)

1...Kc1 2.c2 Kd2 3.c3+ Kd3 4.c1=B bxc3#

Illegal position: black pawn formation is impossible.

View in Helpmate Analyzer

FEN: 8/8/8/ppp5/pkp5/ppp5/1P6/1K6

External links:

PDB: P1235210

Kemp, Charles Edward

The Fairy Chess Review, 1952

h#4 (2+8)

1.Rd4 Kxb5 2.Kd7 Rxb7 3.Kc8 Kxc6 4.Rd8 Rxc7#

Illegal position: no legal last move for White (BTM).

View in Helpmate Analyzer

FEN: 1r6/1rb5/KRrk4/1rb5/1r6/8/8/8

External links:

PDB: P0515211

Burbach, Johannes Jacob

Sanderse, Jacobus Theodorus

Problemas, 1983

h#3* (3+5)

1...Sxb6 2.Ba7 Sc8 3.Bb6 Se7#

1.Ba7 Sxc7 2.Bb8 Sa6 3.Bc7 Sb4#

Illegal position: it is impossible for the bB to reach b8.

View in Helpmate Analyzer

FEN: Nb6/1pp5/1pk5/3R4/K7/8/8/8

External links:

PDB: P0563341

Funk, Klaus

Problemkiste, 1992

h#3 (7+3)

1.Qxb1+ Ka3 2.Qh1 Qe1 3.Qb7 Qe8#

Illegal position: it is impossible for the wB to reach b1.

View in Helpmate Analyzer

FEN: 2k5/2p5/8/8/1P6/1P6/KPP5/QBq5

External links:

PDB: P1340781

Garai, Toma

Buletin Problemistic, M. Manolescu-60 JT, 1999

6th HM

h#3 b) wSb4→e5 (7+15)

a) 1.Qxb2 Bc1 2.Qxa3 Bxa3 3.Re6 Sd5#
b) 1.Qxe3 Re2 2.Qxe4 Rxe4 3.Sf6 Sg6#

Illegal position: 8 black pawns + promoted bishop h5.

View in Helpmate Analyzer

FEN: 3rn3/1p1pkp2/3r4/7b/1N1pPp2/PPpnBp2/1R1q1p2/5K2

External links:

PDB: P0583710

Navon, Emanuel

Sabra Tourney, 2004

4th Prize

h#2 2.1... (8+15)

1.cxb4 Qe1 2.b3 c4#
1.Bxd5 Qh1 2.Be6 Sxd6#

Illegal position: more captures by White are necessary than black pieces are missing.

View in Helpmate Analyzer

FEN: 8/5q2/p1Pp1rr1/BkpP1pp1/nP1pN1pQ/2PK4/b7/b2n4

External links:

PDB: P1073819