lidraughts.org/training/532

@Pontel
What do you mean exactly? Do you mean that the Engine evaluates the position as equal?

In the position, black has a serious problem without the combination. After the combination, black gets an advantage of approximately -0,9. And if you look deeper (after the shot to King), white can capture the King, but only ending up being one piece down.

What's the main variant? Black wants to force white to give three pieces to capture the king, but it seems like white may only have to give two, leading to an equal 9x9: after the king shot, white can play 8.37-32 50-17A 9.42-38 17-26* 10.32-27 and it looks like black cannot prevent the plan 11.38-32 and 12.41-37, except by giving another piece. A: 8..50-39 9.42-38 and black has to give up the king, because of 39-25 10.49-43+

Most important is the fact that if black does not make the combination, black will lose a piece with an evaluation of at least +1 obviously. So, also important in a game, sometimes you need to find the only move not to lose.

Looking at the continuation:
After the combination, with deeper analysis, it is extremely difficult for black to remain an advantage (or keeping it equal). Black probably needs to sacrifice another piece to keep chances, if white is able to find the best moves. The tension is high in the position and both players can easily go wrong every move.

Possible line: 8. 37-32 50-17 9. 42-38 17-26 10. 32-27 3-9 11. 27-22 9-13 resulting in an unclear position for both players.

I'm still curious where the -0.9 comes from. I missed 10.3-9, but after 11.27-22 9-13 white can play 12.47-42 and it seems black needs to give another piece. Seems like draw to me (which is obviously better than losing)

The -0.9 evaluation is from scan after finishing the shot. But this is after a few seconds of evaluating. If you give scan minutes to calculate, it drops to -0.2.

Oi amigos @BumperBalloonCars e @Arkun.

Após exaustiva análise no Scan3.0 e KingsRow, pode-se afirmar que realmente a partida está ganha para as pretas. Segue:

[Event "Game 1, opening start position 1"]
[Date "2019.03.25"]
[White "Kingsrow 1.60a"]
[Black "Scan 3.0"]
[Result "0-2"]
[FEN "B:W23,28,31,33,34,35,36,38,39,40,41,42,44,45,46,47,48,49:B1,2,3,4,6,7,8,9,10,11,13,15,16,19,20,21,24,25"]

1. ... 24-29 2. 23x5 20-24 3. 34x23 9-14 4. 5x30 25x32 5. 28x37 21-27 6. 31x22 13-18 7. 22x13 8x50 8. 42-38 50-17 9. 37-32 17-26 10. 32-27 16-21 11. 27x16 3-9 12. 47-42 26-3 13. 41-37 11-17 14. 40-34 15-20 15. 37-32 7-12 16. 46-41 12-18 17. 41-37 9-13 18. 37-31 20-24 19. 49-43 24-29 20. 34x21 3x28 21. 35-30 28-19 22. 30-25 19-28 23. 36-31 28-22 24. 31-26 22-28 25. 45-40 13-18 26. 40-34 28-23 27. 34-30 23-19 28. 30-24 19x35 29. 38-32 35-19 30. 16-11 19x46 31. 11-7 2x11 32. 42-38 46-28 33. 26-21 11-16 34. 21-17 28x11 35. 38-32 11-33 36. 25-20 33x15 37. 43-39 18-22 38. 39-34 15-42 39. 48x37 22-27 40. 32x21 16x27 41. 34-30 4-10 42. 37-32 27x38 43. 30-25 10-14 44. 25-20 14x25

________

[Event "Game 2, opening start position 1"]
[Date "2019.03.26"]
[White "Scan 3.0"]
[Black "Kingsrow 1.60a"]
[Result "0-2"]
[FEN "B:W23,28,31,33,34,35,36,38,39,40,41,42,44,45,46,47,48,49:B1,2,3,4,6,7,8,9,10,11,13,15,16,19,20,21,24,25"]

1. ... 24-29 2. 23x5 20-24 3. 34x23 9-14 4. 5x30 25x32 5. 28x37 21-27 6. 31x22 13-18 7. 23x12 8x50 8. 42-38 50-17 9. 37-32 17-26 10. 32-27 16-21 11. 27x16 3-9 12. 40-34 26-3 13. 41-37 9-13 14. 47-42 13-19 15. 37-32 15-20 16. 34-30 19-23 17. 49-43 11-17 18. 30-25 4-9 19. 25x14 9x20 20. 46-41 20-25 21. 36-31 3-20 22. 43-39 20-15 23. 39-33 15-24 24. 41-36 23-29 25. 42-37 17-22 26. 48-42 25-30 27. 31-27 22x31 28. 37x26 30-34 29. 42-37 6-11 30. 33-28 24-19 31. 36-31 19-13 32. 32-27 11-17 33. 38-32 13-8 34. 26-21 17x26 35. 28-22 7-11 36. 16x7 1x12 37. 22-17 12x21 38. 27x16 2-7 39. 31-27 34-39 40. 32-28 39-44 41. 28-22 44-49 42. 22-18 49x21 43. 16x27 29-34 44. 27-22 8-2 45. 45-40 34x45 46. 35-30 2x35 47. 22-17 45-50 48. 17-12 7-11 49. 12-8 35x2 50. 37-32 2-8 51. 32-27 11-16 52. 18-13 8x19 53. 27-22 50x17 *

Very nice you checked it out like this! So it is clear that the combination is the best way to proceed the game and that the puzzle is good.

Quite surprising and interesting that both engines win with black. Although the evaluation is mostly slightly better for black, it is far from clear how this is translated in a game when played further.

Google translate (@Pontel):
Muito bom você verificou isso! Então fica claro que a combinação é a melhor maneira de continuar o jogo e que o quebra-cabeça é bom.

Bastante surpreendente e interessante que ambos os motores ganham com preto. Embora a avaliação seja na maioria das vezes melhor para o preto, está longe de ser claro como isso é traduzido em um jogo quando jogado ainda mais.