Hey, thanks for the original post! I was not able to find article about Vampires on Andrew Buchanan's site. Apart from the starting position, any canonical/famous vampire position?
I would say the "official" solution to Andrew's challenge (finding a vampire where en-passant is possible) is another one that deserves attention.
I'm planning to continue this topic with 2 more blog posts in the coming days.
There, you'll have the opportunity to see many more examples, some of them very complex and exciting!
I'm planning to continue this topic with 2 more blog posts in the coming days.
There, you'll have the opportunity to see many more examples, some of them very complex and exciting!
@Solal35 There is indeed a section in Andrew's site where you can find inspiration: http://anselan.com/MOD.html
Thanks for the article, I didn't know about vampire positions.
I tried to find a proposal that I think is vampire.
White people play,
White and black are entitled to both castlings (so the white and black rooks have not moved),
White can take en passant (so the last move is b5).
r1bqkb1r/p1pppppp/8/1pP5/8/5N2/1PPPPPPP/RNBQKB1R w KQkq - 0 1
lichess.org/editor/r1bqkb1r/p1pppppp/8/1pP5/8/5N2/1PPPPPPP/RNBQKB1R_w_KQkq_-_0_1?color=white
1. a3 Nc6 2. Nc3 Nb4 3. axb4 Nf6 4. Nb1 Ne4 5. Nf3 Nc5 6. bxc5 b5
I tried to find a proposal that I think is vampire.
White people play,
White and black are entitled to both castlings (so the white and black rooks have not moved),
White can take en passant (so the last move is b5).
r1bqkb1r/p1pppppp/8/1pP5/8/5N2/1PPPPPPP/RNBQKB1R w KQkq - 0 1
lichess.org/editor/r1bqkb1r/p1pppppp/8/1pP5/8/5N2/1PPPPPPP/RNBQKB1R_w_KQkq_-_0_1?color=white
1. a3 Nc6 2. Nc3 Nb4 3. axb4 Nf6 4. Nb1 Ne4 5. Nf3 Nc5 6. bxc5 b5
Very nice, @Kmenbert , you are definitely on the right track!
You are using the castling and en-passant flags perfectly to limit the movement of pieces as you need.
Your position is not a vampire because the pawn on c5 may have captured on same-color squares (b4 & c5 or b3 & c4) or different-color ones (b3 & c5). This breaks the parity invariant.
For the mirror image:
1. Nc3 Nc6 2. Na4 Nb8 3. Nb6 axb6 4. Nf3 b5 5. Ne5 Nf6 6. Nc4 bxc4 7. b4
You are using the castling and en-passant flags perfectly to limit the movement of pieces as you need.
Your position is not a vampire because the pawn on c5 may have captured on same-color squares (b4 & c5 or b3 & c4) or different-color ones (b3 & c5). This breaks the parity invariant.
For the mirror image:
1. Nc3 Nc6 2. Na4 Nb8 3. Nb6 axb6 4. Nf3 b5 5. Ne5 Nf6 6. Nc4 bxc4 7. b4
yes indeed, the paths b4-c5 or b3-c5 of the pawn are possible and it is therefore not a vampire position (even if it seems to me that the path b3-c4 is impossible)
Well, I will search later,
THANKS
Well, I will search later,
THANKS
Yeah, you are right! b3-c4 is not possible because Black would run out of knights (and moves to make) before the pawn can reach c5.
Very nice!
Very nice!
Thanks for your advices.
Well finally, I'll try again: I think this position is vampire, with grip en passant.
It's white's turn to play,
All 4 castlings are possible
THANKS
r1bqkb1r/1pp1p1pp/p7/3pP3/8/8/PPPPPPP1/RNBQKB1R w KQkq d6 0 12
1. Nf3 Nf6 2. Ng1 Nh5 3. Nf3 Ng3 4. hxg3 Nc6 5. Ng1 Nd4 6. Nf3 Ne6 7. Ng1 Nf4 8. Nf3 f6 9. Ne5 fxe5 10. gxf4 a6 11. fxe5 d5
Well finally, I'll try again: I think this position is vampire, with grip en passant.
It's white's turn to play,
All 4 castlings are possible
THANKS
r1bqkb1r/1pp1p1pp/p7/3pP3/8/8/PPPPPPP1/RNBQKB1R w KQkq d6 0 12
1. Nf3 Nf6 2. Ng1 Nh5 3. Nf3 Ng3 4. hxg3 Nc6 5. Ng1 Nd4 6. Nf3 Ne6 7. Ng1 Nf4 8. Nf3 f6 9. Ne5 fxe5 10. gxf4 a6 11. fxe5 d5
That's goddamn close! I'm confident you'll get it in your next attempt. :)
Now you made sure the Black knights were captured on dark squares. However, these squares could have been (g3 & f4) or (g3 & e5). There are a few ways to reach the mirror image:
1. Nf3 Nf6 2. Ne5 Ne4 3. Ng6 Nc3 4. Nxc3 hxg6 5. a3 Nc6 6. f4 Nb8 7. f5 gxf5 8. Ne4 fxe4 9. d4
You also need to make sure to control the square color where the White knight is captured. Even assuming wN has been captured by the bPf7, there are two options: on e6 or on e5. This leads to another mirror line:
1. Nf3 Nf6 2. Nh4 Nd5 3. Ng6 hxg6 4. Nc3 Ne3 5. fxe3 Nc6 6. Ne4 Nb8 7. Ng3 Nc6 8. Nf5 gxf5 9. e4 fxe4 10. a3 Nb8 11. d4
Now you made sure the Black knights were captured on dark squares. However, these squares could have been (g3 & f4) or (g3 & e5). There are a few ways to reach the mirror image:
1. Nf3 Nf6 2. Ne5 Ne4 3. Ng6 Nc3 4. Nxc3 hxg6 5. a3 Nc6 6. f4 Nb8 7. f5 gxf5 8. Ne4 fxe4 9. d4
You also need to make sure to control the square color where the White knight is captured. Even assuming wN has been captured by the bPf7, there are two options: on e6 or on e5. This leads to another mirror line:
1. Nf3 Nf6 2. Nh4 Nd5 3. Ng6 hxg6 4. Nc3 Ne3 5. fxe3 Nc6 6. Ne4 Nb8 7. Ng3 Nc6 8. Nf5 gxf5 9. e4 fxe4 10. a3 Nb8 11. d4