Hard positions posted for 6 last moonths

[Vinvin]

It's easier for me to group positions in a single message.

Chessbase repost this one this week : https://en.chessbase.com/post/darkness-on-the-horizon-2
http://talkchess.com/forum3/viewtopic.p ... 7&p=677665
[d]8/1p6/1Pp2N1q/p1Ppk2p/P3p3/3PPpPp/3K1P1P/2R5 w - - bm Ng4+


http://talkchess.com/forum3/viewtopic.p ... 34#p840634
[d]r4rk1/pq4bp/np1P1pp1/2p3B1/Q7/5N2/P4PPP/1R1R2K1 w - - bm d7;


http://talkchess.com/forum3/viewtopic.p ... 01#p839301
[d]r2q1k2/1pb2p1n/1Pp4r/P2p3p/3Pp1p1/2B1P3/4BPPP/1R1Q1RK1 b - - bm Bxh2;


http://talkchess.com/forum3/viewtopic.p ... 53#p823353
[d]r3kb1r/1p4pp/2q1pp2/1p2Q3/8/2P5/PP2B1PP/R4R1K w kq - bm Rxf6;


http://talkchess.com/forum3/viewtopic.p ... 77#p830177
[d]2r1bq1k/2r2p1P/1p2pPp1/p2pP1N1/3P4/nPP5/R2Q2K1/2RN4 w - - Rxa3;


http://talkchess.com/forum3/viewtopic.p ... 76#p829476
[d]k1b5/1p1p4/p1bP4/PP6/8/6N1/8/K7 w - - 0 1 bm b6;


http://talkchess.com/forum3/viewtopic.p ... 74#p829474
Which engine gives an eval under 0.5 here ?
[d]4kb2/2p3r1/1pP1P2Q/pP2K3/P7/8/8/8 w - - 0 93;


http://talkchess.com/forum3/viewtopic.p ... 73#p829473
This position still not easy (sometimes more than 1 minutes with 4 cores) for today : Rxf7!!
[d]r1b1r1k1/1pBnnpp1/p1q1p2p/8/4N3/6Q1/2PRB1PP/5R1K w - - bm Rxf7;


http://talkchess.com/forum3/viewtopic.p ... 37#p844437
[d]r1bqk1nr/pp1pnppp/1bp5/1B6/3PP3/5N2/PP3PPP/RNBQ1RK1 w kq - bm d5;

[Dann Corbit]

Vinvin is so wonderful, if he did not exist, we would have to invent him.

[Vinvin]

Adding a couple more :

From http://talkchess.com/forum3/viewtopic.p ... 21#p845021
1. Bxf2! Nxc5 2. Bg1! Nxa4 3. Nd1!!
[d]7k/8/7K/p1P1p1p1/B7/3nN1p1/5r2/6B1 w - - bm Bxf2;


From http://talkchess.com/forum3/viewtopic.p ... 24#p835424
12. Nxe5?? Nxe5 13. Rxe5 Nf4!! 14. Nf3 Nxg2!!
[d]7k/8/7K/p1P1p1p1/B7/3nN1p1/5r2/6B1 w - - am Nxe5;

[Dann Corbit]

I think the board is wrong (same as above?) because the knight is on the wrong square to capture

[Vinvin]

Correction, the board was wrong.
Thanks to Dann !

From http://talkchess.com/forum3/viewtopic.p ... 24#p835424
12. Nxe5?? Nxe5 13. Rxe5 Nf4!! 14. Nf3 Nxg2!!
[d]r4rk1/1bpqbppp/p1n5/1p1np3/8/1B1P1N1P/PPPN1PP1/R1BQR1K1 w - - am Nxe5;

[Vinvin]

Some more :

5 positions from here : http://talkchess.com/forum3/viewtopic.p ... 25#p846325
2nd position is the hardest. 5th position is the easiest.

5N1n/3P1p1p/5P1k/1Pp1P2p/4KP1P/2p5/p4b2/5N2 w - - bm Ne3;
k7/P4pp1/1P6/2p1P3/2P1n3/p5pB/P4n2/K5b1 w - - bm e6;
2k5/p2p4/1P6/P3p3/1q2N3/2p5/K7/7Q w - - bm Nd6+;
7k/pp1pBp1N/1p3Pp1/b3K1PR/P3P2p/R1n4P/2P1N1P1/3q4 w - - bm Rxc3;
4kb2/Rpn1p1rP/1P1pBPN1/4p3/4P1Qn/3b4/1r2R1K1/3qN3 w - - bm Kg3;


1 positions from here http://talkchess.com/forum3/viewtopic.p ... 71#p845871
(3 positions but one already in the hard-set and the other one is incorrect.)
r2bbrk1/1q4pn/2np1p1p/2pNpP2/ppP1P1PP/3P1BQ1/PP1BNR2/R5K1 w - - bm Kh1;


One from the Rybka forum : http://rybkaforum.net/cgi-bin/rybkaforu ... ?tid=33528
3q1rk1/r2nbp1p/2p1p1pP/p1Nn4/3PN3/8/PPQB1PP1/1K1R3R w - - bm g4;


A game with full of deep moves : http://talkchess.com/forum3/viewtopic.p ... 18#p846918

[Pafifi]

The Rybka form puzzle
[pgn]
[FEN "3q1rk1/r2nbp1p/2p1p1pP/p1Nn4/3PN3/8/PPQB1PP1/1K1R3R w - - 0 1"]

1. g4 a4 (1. .. Nb4 2. Qc3 Nxc5 3. dxc5 f6 4. Bf4 Nd5) *
[/pgn]
Didn't see the winning line … My laptop SF insists on drawish …

[Vinvin]

2 more positions :

1)
From http://talkchess.com/forum3/viewtopic.p ... 31#p847031
[d]1rb1r3/5qk1/3b2p1/1PnPp1Pp/4B3/pP3Q2/P2N1B1P/1KR3R1 b - - bm Qxf3;


2)
From http://talkchess.com/forum3/viewtopic.p ... 22#p842722
Find a 0.00 eval for his position :
[d]3n1k2/2p1b3/B1R1PP2/2Nb4/2p5/pr4Rp/1PP2prP/4NK2 w - - 0 1;

[Vinvin]

2 more positions :
1)
From http://talkchess.com/forum3/viewtopic.p ... 78#p845278
[d]7k/8/7K/p1P1p1p1/B7/3nN1p1/5r2/6B1 w - - bm Bxf2;

2)
From http://talkchess.com/forum3/viewtopic.p ... 83#p852083
[d]rnbqk2r/pp1p1ppp/3P1n2/b1p5/8/2N2N2/PP2PPPP/R1BQKB1R w KQkq bm e4;

[MMarco]

The Rybka form puzzle
[pgn]
[FEN "3q1rk1/r2nbp1p/2p1p1pP/p1Nn4/3PN3/8/PPQB1PP1/1K1R3R w - - 0 1"]

1. g4 a4 (1. .. Nb4 2. Qc3 Nxc5 3. dxc5 f6 4. Bf4 Nd5) *
[/pgn]
Didn't see the winning line … My laptop SF insists on drawish …

It is not all that clear at depth=30 that g4 is best according to SFNNue + SV-2051:

Code: Select all

[30] 1.08 g4 Cb4 Dc3 Cd5 Dc4 a4 The1 a3 b3 C7b6 Dc1 Db8 Dc2 Cd7 g5 Cxc5 dxc5 Dh2 Fc1 f6 f4 Dxc2+ Rxc2 fxg5 fxg5 Tf5 Cd6 Fxd6 cxd6 Rf7 Rd3 Td7 Fxa3 Txg5 Rc4 Tg2 Rc5 Cf6
[30] 1.06 Ca4 Db8 Tc1 C7f6 f3 Db5 Dc4 Td8 a3 Cxe4 fxe4 Cf6 The1 Cg4 Dxc6 Dd3+ Dc2 Dxd4 Ff4 Df6 Tf1 e5 Fd2 Dh4 Cb6 Tb7 Cc4 Tdb8 Ra1 Cf2 Cxe5 Txb2 Dxb2 Txb2
[30] 0.84 Tc1 Cb4 Dc4 Cb6 Db3 Dxd4 Fe3 De5 f3 C6d5 Ff2 f5 Cc3 Tb8 Cxd5 Dxd5 a3 a4 Dxd5 Cxd5 Fd4 Taa8 Ra1 Rf7 The1 Fxc5 Txc5 Ta6 Tb1 Tb5 Tbc1 Txc5 Txc5 f4 Tc4
[30] 0.77 f3 Cxc5 dxc5 Db8 a3 De5 Fc1 Tb7 Ra2 Tfb8 Cd6 Fxd6 cxd6 f5 Ra1 Dxd6 Dc4 Rf7 The1 e5 Td2 Te8 Tc2 Te6 Da6 Dc7 Tc5 Db6 Dxb6 Txb6 Txa5 Tb5 Ta6 Tc5 b3
d:31/54 1:g4 t:2089 n:560M nps:268k tb:27 h:100

Deeper analysis is needed!