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Chessengeria's Chess Engines Elite Tournament - 2023

What's the best way to celebrate the end of 2023 in Chessengeria style?

Of course, by organizing a tournament of the absolute chess engines elite ;)

This entry will be in a somewhat humorous tone and more in a relaxed vein than most of the content on chessengeria.eu. After all, I'm celebrating the new year on the pages of our blog :)

The strongest versions of the engines that have reached at least 3500 Elo on the *MCERL rating list have been invited to participate in this unique tournament.

Only about 3% of chess engines, of which there are exactly 15, can boast such tremendous strength.

Here is the list of participants in alphabetical order:

Here is the list of participants in order of Elo rating, from the strongest:

The average Elo of players at a high level of 3625 indicates that there are no random players, weak and untested engines among the participants. All of them are real "tough guys", who in many battles (thousands of games) have proven their belonging to the heavyweight category of computer chess players.

The tournament was run under the terms of MCERL, that is:

Each engine played 10 games with every other engine, making a total of 1050 chess games in this tournament. The tournament began on December 31, 2023 and ended on January 1, 2024 just after midnight.

The winner was determined with literal fireworks going on :)

Which chess engine will prove to be the winner? Which one will play the most interesting and spectacular game? Which one will impress by defeating its opponent in the shortest duel?

Before we delve into the coverage of the tournament, a few words about the participants.

Of the 15 players:

as many as 14 are development engines whose successive versions have been released over the past year. The exception in this group is the Revenge engine, which came out in as late as 2022, and still, despite the passage of more than 1 year, it plays with the strength to participate in the Elites tournament. The Seer 2.6 engine is a development version, just before the release of Seer 2.7 in October 2023.
2 participants are commercial engines. Only two: Dragon by Komodo Chess and the aforementioned Revenge.
12 participants are open-source engines.
Only 3 engines do not share their sources, commercial Dragon By Komodo Chess and Revenge as well as free rofChade.

This paints a picture of a very healthy situation in the world of the most powerful chess engines at the end of 2023. Most of the authors of chess engines and the communities around them take a transparent approach to sharing sources and sharing their knowledge and experiences. Anyone interested can trace how Stockfish, Berserk, or RubiChess, for example, is created. And it works! Every day newer versions of engines are published, almost every week new ones are presented. C, C++, C#, Go, Java, Pascal, Rust, Zig and others - various programming languages are being used in increasing numbers to create chess engines.

I would venture to say that the community interested in computer chess is increasingly active, and the creation and development of chess engines is gaining popularity.

And maybe, just maybe... chess engines have never played so great chess before :)

What I will show you dear reader with examples from the 2023 Elite tournament.

Category: fastest victory - Dragon 3 By Komodo Chess

White: rofChade 3.1

Black: Dragon 3 by Komodo Chess

Game length: 25 moves

Black's 22nd move.

What is there to write, the whites stand at a loss. This is the result of their several poor decisions on the Queen's wing.

22...Nf4!

Dragon does what is expected of an engine with 3700 Elo on its counter - it natively exploits weaknesses near the white King.

Three more moves and black checkmate the white King.

23.Qb2

Resistance was prolonged by 23.gxf4 with a possible continuation: 23...exf4 24.Hf3 Qh6 25.Qh3 Bd4+ 26.Be3 Qg7 27.Bxd4 Qxd4+ 28.Ne3 f3!!

rofChade probably decided (rightly) that further play would not provide a chance for survival in this game, and thus ensured Dragon by Komodo Chess victory not only in this skirmish but also in the category for the shortest game ;)

23...Qh6

And two moves to checkmate white King.

24.Bd3

Frees up the f1 square for the King.

24...Qh2+

25.Kf1

25...Qh1#

The end of this game.

25 moves, it's almost a chess miniature.

As you can see, and at this level, it is possible to finish quickly.

Download game: Fastest victory_rofChade 3.1 vs Dragon 3 by Komodo Chess

Category: most spectacular finish - Seer 2.6.0

Game 1

White: Seer 2.6.0

Black: Dragon 3 by Komodo Chess

White's move.

The name of the category speaks for itself, so - let's start crashing!

24.Nfxe5!

24...dxe5

Dragon must accept the sacrifice.

25.Rxe5 Re8

26. Bxh7!

26...Kxh7

Again, the sacrifice must be accepted, otherwise the situation will become even worse for blacks.

27.Nf6+!!

Another third sacrifice, and this time it should also be accepted, otherwise there will be checkmate of the black King in two moves (27...Kg6 28.Qh5+ Kxf6 29.Qf5#).

27...Qxf6

28.Qh5+

Seer includes his Queen in the immediate development of events. White has three fewer pieces.

28...Kh7

29.Rg5+ Kf8

30.Rf5

White's last move put the black Queen in a lost position. Soon Seer will begin to make up material losses without letting the opponent's King breathe for a moment.

30...Bd8

Dragon was left with few options.

Due to black's stubbornness in continuing this lost game, the game lasted several dozen more moves. Probably Dragon by Komodo Chess couldn't get out of the shock that another engine, which is not Stockfish, could win with it in such a style ;)

Below are some final moments of this skirmish:

35Qxf5+

41.Qxd6

55.Bd4

61.Be3#

Absolute destruction...!

A big applause for the Seer chess engine :)

This is probably not what Dragon By Komodo Chess expected when playing against a theoretically weaker opponent.

Download game: Most Spectacular Finish_Game_1_Seer 2.6.0 vs Dragon 3 by Komodo Chess

Category: most spectacular finish - RubiChess 20231230

Game 2

White: RubiChess 20231230

Black: Seer 2.6.0

White's move.

And this time one of the participants in an interesting game is the Seer engine, although by a twist of fate, it is to RubiChess in this skirmish that the chess goddess smiles ;)

23.Rxg7+!

RubiChess smelled "chess blood".... No discount - smash the defense and get to the opponent's King!

23...Kxg7

What's next? How to lead the attack, maybe 24.Bxh6+ or 24.Re3, hmmm.... Are white sure they've calculated their forces well against their intentions?

24.Nxd6!

This is an important and meddlesome move. Knight is invulnerable, if black decides to take the white Knight 24...Qxd6 then in response 25.Bxh6+ with the loss of the black Queen in the next moves.

24.Kh7

The Black King steps off the square of fire of the white Bishop (h6).

25.Bc3

Perfectly timed. White Bishop does nothing on the h6 square, changes his position occupying the best diagonal at that moment.

25...Ng6

26.Qd4

increasing the pressure on Knigt f6 and creating potential checkmate threats on the g7 square.

26...Nh5

27.Bxg6+ Kxg6

28.Rxe4!!

A unique sacrifice of the white Rook. RubiChess throws all its forces into the attack.

28...Qe7

Correct. If 28...fxe4 then 29.Qxe4+ Kg5 30.h4#

29.Nxf5!

29....Rxf5

Any other move by the blacks leads to a faster defeat.

30. g4 Qg5

31.h4

Cool position, two white pawns attack three black pieces.

This is great illustration of the meaning of a chess attack on the position of the opponent's King. Even if not everything can be counted, in the situation when one or more foreign pieces do not participate in the defense, then it is worth the risk.

31...c5

32.Qd1 Rd8

33.Qb1 Qe7

34.gxf5+

Taking a pawn leads to checkmate in three moves: 34...Kxf5 35.Re5+ Kg4 36.Qf5+ Kxh4 37.Qxh5#

34...Kh7

35.f6

White dominance. Two advanced Pawns and the exposed position of the black King.

35...Nxf6

36.Rf4 Kg8

37.Bxf6

Black got the checkmate within a few moves.

46.h5#

This is what a chess engine with over 3700 Elo on the strength meter is capable of, precise, unforgiving, making maximum use of available resources - this is what RubiChess is !

Download game: Most Spectacular Finish_Game_2_RubiChess 20231230 vs Seer 2.6.0

Category: most interesting game - Black Marlin 8.0

White: Black Marlin 8.0

Black: Alexandria 5.1.1

12.d5

Black Marlin chose the Spanish game, a closed variant (Chigorin). This system is often characterized by complex play, full of figurative maneuvers with many opportunities for both sides.

14...Ne8

First little surprise.

In these kinds of positions, usually black decides, for example, ...Nfd7 or ...c4 to initiate developments on the Queen's wing (occupation of the c5 square by Knight, etc.).

Whether Alexandria plans to ...f5 in the future, we will see.

15.a4

Better than passive Nbd2.

17...Rb8

Black is playing actively. More and more opportunities are born on the chessboard.

19...f5

And yet! This is a much more interesting than 19...Nb3 or 19...h6.

Pawn's temporary sacrifice on f5 is intended to weaken the important d5 square on which white Pawn stands. If black succeeds in occupying this square, it may gain an advantage by breaking up Chigorin's closed variant.

20.exf5

Not accepting black Pawn could weaken white's abilities on the King's wing, such as 20.Bg5 and strong 20...f4!

20...h6

21.Nd2 Bg5

22.g4 Bxd2

23.Bxd2 c4

The situation is escalating.

In the meantime, white defended its Pawn f5 and started offensive actions through 22.g4. Black, on the other hand, set up exchanged their weak black-square Bishop for a strong Knight d2 and set up better and better squares.

24.Be3 Bb7

25.Rad1 Nf6

26.Qf3

Black strengthens the pressure on the d5 square. White defends this square where their Pawn stands.

26...Ba8

27.Kh2 Rb2!=

The position is balanced, although increasingly complicated.

As correct a heavy figure move as possible; perhaps hoping for 28.h4 which would allow black to play a strong 28...e4!

28.Bc1 Rbb8?!

Black's first a weaker move. Rook's retreat is a loss of tempo.

Better to brave 28...Ra2! and accept the loss of Rook in exchange for Bishop but in keeping with the spirit of breaking Chigorin's variant, Alexandria could gain the important point on the chessboard that is d5.

Possible continuation: 28...Ra2! 29.Bb1 Ra1 30.Bb2 Rxb1 31.Nxb1 Nb7 32.Ba3 Nd8 33.Nd2 Bxd5 -> with equal position (2 free and strong black Pawn in the center)

Diagram formed after 33...Bxd5 at the end of a possible continuation

Back in the game.

29.g5

Black Marlin immediately seizes the opportunity and launches offensive operations on the King's wing.

29...hxg5

30.Rg1 Qc5

31.Rxg5 Bxd5

Alexandria finally managed to capture a key point on the chessboard - d5. So should black be satisfied with the position obtained? Comparing the current position to the position obtained at Rook's price (diagram above), I think not. Now white has a highway for its heaviest figures leading directly to the black King.

Anyway, it's getting more and more interesting, with both sides having a lot of possibilities.

32.Qg3 Rf7

33.Rg1 Rb7

In response to the powerful white pressure, black defends Pawn g7 by doubling on the seventh line both Rook; this is not the end of their possibilities - the black Queen can also join in to support the defense from the c7 square. Black's defense seems to be strong enough to protect their King.

This kind of position is such a good illustration of how an early loss of one tempo can enable the other side to take the initiative.

34.Rg6?!

Like black before, with this move white loses tempo, their onslaught will slow down.

Due to the effective defense of Pawn g7 protecting the black King, it seems more logical to shift their forces to the h-line via 34.Qh4 and attach the future to the play of both Bishops on the c1-h6 and d1-h5 diagonals.

34...Nc6

35.Qh4 e4!

Good move! Limits the white Bishop c2 and frees the e5 square for the black Knight.

In my opinion, the position is close to full equalization. Some chess engines indicate white's advantage, although after a longer analysis it is clear that black is able to hold.

36.Rh6

Another interesting move was 36.Bd1, which led to further maneuvers.

36...Kf8=

The perfect moment to reposition the black King. The position is equal.

This is the culmination of this game.

The white's efforts, while ingenious, have not yet given them a decisive advantage.

Black, on the other hand, having lost tempo earlier, activates his forces in the last moves and improves its position from move to move.

Unless Black Marlin does something decisive, the game will end in a draw at best, yet there is no shortage of weaknesses in his camp: Pawn f2, f5, Knight a3 out of play.

37.Rxg7!!

What an impact, what a sacrifice :)

Two exclamation marks for this move, not because it's a finishing and winning move, but because it's the only one that gives white a chance to win. A beautiful move, a risky move, a creative move - one that can bring out the balance, one that can lead to a win.... or a loss.

Black Marlin throws the gloves in Alexandria's face.

37...Kxg7?

The mistake that white was waiting for. Probably black was counting on 38.Rh8 Qxf2+ 39.Qxf2 Kxh8=)

The balance was maintained by 37...Rxg7! with a possible continuation 38.Qxf6+ Kg8 39.Be3 Qxa3 40.Qh4 Rh7! 41.Bxe4 Bxe4 42.Rxh7 Rxh7 43.Qxe4 Qxc3 44.Qe8+ Kg7=

38.Be3!+-