Illegal Position Contest!
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CaptainHookCharge wrote:
This is SPARTA!
As white starts the game it would be finished even before start of the game due to stalemate of white.
CookedQueen wrote:
CaptainHookCharge wrote:
This is SPARTA!
As white starts the game it would be finished even before start of the game due to stalemate of white.
Huh? He still has plenty of pawns to move
RealSans wrote:
Best shot at yin yang
This is yin yang
Clearly illegal
The Smiley. With moustache. 
Trump Failure. White is trying to attack black.
Is this illegal?
Jan 31, 2017
0
#156
MGleason wrote:
Quoting 161. that's not a position, that's a board.
Jan 31, 2017
0
#158
illegal position
(proof: Assume this position was legal. Then it could have only occured if white's a-pawn has captured one black rook and if black's a-pawn has captured one white rook.
Before White captured one black rook with his a-pawn, the a-pawn was either on a2 or on a3, meaning that it hasn't reached the 4th rank. Also, all other white pawns are either on 2nd or on 3rd rank, meaning that they never have reached the 4th rank. Hence, before White captured the black rook, all of his pawns were sitting either on 2nd or on 3rd rank. But then, there is no way for one white rook to maneveur out of the white pawn chain so that it could be captured by the black a-pawn. Therefore, white must have captured the black rook before black captured the white rook.
Analogously, however, one obtains that black has captured the white rook before white has captured the black rook, contradiction.)
Jan 31, 2017
0
#160
@GMPatzer because white and black must have played exactly the same number of moves. The only possible moves are knight moves and shuffling the rooks back and forth one square.
Each rook must have moves an even number of times (including zero as a possibility).
Also, for knight moves, each side must have either moved both knights an even number of times (including zero as a possibility), or both knights an odd number of times (if they switched places), for a combined even number. Remember that a knight must switch colours every move, so an even number of moves will land it on its original colour, and an odd number of moves will be on the opposite colour.
Since rook moves and combined knight moves must both be even numbers, there is no way for white to have played an even number of moves and black an odd number, or vice versa. Therefore, that position, with black to play, is impossible.