We witness a fantastic tactical episode from Stockfish against Leela. Black’s king is caught in the centre and its kingside pieces are undeveloped but it isn’t clear how to transform these dynamic advantages into something concrete. Stockfish shows the way! Lots of useful tactical motifs to drill into your head here – they will certainly come in handy in your games!

This position was reached after move 29 of the Stockfish-Leela Season 18 SuperFinal, game 52 (https://tcec-chess.com/#div=sf&game=52&season=18). After an offbeat opening, Leela had continued in HyperModern vein by omitting to develop any more of its kingside pieces! Despite that, there was method to Leela’s madness as it proved difficult to get at Black’s position. However, with the breakthrough on the b-file, Stockfish was launched on the path to glory! White not only controls the b-file, there is also a lateral attack on the e6-pawn. Leela’s …f6 looks to realize the exchange of queens after which the danger to the black king will be greatly reduced. Stockfish… has other plans!

30.c5!!

Threatening c6, undermining Black’s protection of the e6–pawn in front of its king.

i) 30…Bxc5 is impossible due to 31.Qxg7; meanwhile

ii) 30…Qxc5 31.Nxe6 dxe6 32.exf6

is catastrophic for Black. Rxe6+ and Rxe4 is threatened as well as fxg7. 32…Kf7 33.Rb7+ Bxb7 34.Rxb7+ Kxf6 35.Bc3+ e5 36.Qg5+ Ke6 37.Qg6+ Kd5 38.Qf7+ is the beautiful cleanest mate which I’d missed! 38…Kc6 (38…Ke4 39.Qf3#) 39.Qd7#;

iii) 30…fxe5 31.Nxe6 dxe6 32.Rxe6+ Kf7 33.Rxe5 threatening Qb3+ and Rxe4 is the simplest. 33…Kg8 34.Qb3+ Qf7 35.Qxf7+ Kxf7 36.Rxe4 leaves White 2 pawns up

30…Qxe5

The most consistent move, trying to reduce White’s attacking potential with the exchange of queens. Now the tactical theme changes: from the precariousness of Black’s king’s position to its undeveloped kingside pieces.

31.Qxe5 fxe5 32.Rb8 Rxb8

Forced. Black must concede the 8th rank to White. However, White doesn’t have that much firepower left: how bad can it be?

33.Rxb8+ Kf7 34.Nf3

Threatening Ng5+ forking the king and bishop. Black must exchange its only developed piece. However, this capture also gives Black a tempo to relieve the pin on the f8–bishop and threaten to capture the c5–pawn.

34…Bxf3 35.gxf3 Rg8 36.Bb4!!

Protecting the b4–pawn is your first thought. Then you look at Stockfish’s evaluation…+5.35!! …and it starts to dawn on you that there might be more to 36.Bb4!! than first meets the eye. Try and find a move!

36…g5

36…Be7 37.Rxg8 Kxg8 38.c6 Bd8 39.Be7

Beautiful! 39…Bxe7 (39…Bc7 40.cxd7) 40.c7

37.hxg5 Rxg5+ 38.Kh1

It’s quite remarkable that Black has no good way of freeing itself!

38…e4

38…Be7 39.c6 dxc6 40.Rb7 is the cunning idea!; 38…Bh6 39.Rd8 Ke7 40.Rh8 Threatening c6+ when the c-pawn will queen!;

38…Bg7 39.Rd8 Ke7 40.Ra8 Threatening c6 and thus winning the a-pawn with tempo.;

38…Rg8 39.Rd8 Ke7 40.Ra8 is the same trick.

39.c6

39…Bxb4 40.c7

Job done! Stockfish converted easily.

40…Rc5 41.c8Q Rxc8 42.Rxc8 exf3 43.Rc4 Be7 44.Rf4+ Kg6 45.Rxf3 d5 46.Rb3 a5 47.Kg2 Kf5 48.Rb5 Bb4 49.Rxb4 axb4 50.a5 d4 51.Kf3 h4 52.a6 d3 53.Ke3 dxc2 54.Kd2 b3 55.a7 h3 56.a8Q Kg6 1–0