28 January 2023

Commentary: U.S. Women's Championship, Round 3 (Eswaran - Paikidze)

This next commentary game features a positional struggle involving what IM Jeremy Silman terms - usefully, I think - key "imbalances" between the sides. The opening, a Two Knights Caro-Kann, sets this up early, with Black exchanging bishop for knight on move 4. The minor piece and pawn structure imbalances are the main things both sides have to keep in mind for their strategies. It was useful to analyze their choices and see where different options might have kept more tension in the position.

[Event "U.S. Women's Chess Championship 2022"] [Site "Chess.com"] [Date "2022.10.07"] [Round "03"] [White "Eswaran, Ashritha"] [Black "Paikidze, Nazi"] [Result "1/2-1/2"] [WhiteElo "2365"] [BlackElo "2354"] [ECO "B11"] [Annotator "ChessAdmin/Dragon by Komodo 2.6.1"] [TimeControl "5400+30"] 1.e4 c6 2.Nc3 d5 3.Nf3 {the Two Knights Caro-Kann.} 3...Bg4 {the most effective response by Black, who however will need to immediately exchange bishop for knight, as the bishop retreat after h3 is not as effective. This is not a bad trade-off, however, as the Nf3 is a valuable attacking piece and Black will be able to build a strong pawn skeleton on the light squares.} 4.h3 Bxf3 5.Qxf3 e6 6.Be2 Nf6 7.O-O ( 7.e5 {looks tempting, but scores poorly for White, as attacking prospects are limited and Black will get more counterplay in the center. An example game:} 7...Nfd7 8.Qg3 a6 9.O-O c5 10.d3 Nc6 11.f4 g6 12.Kh1 Be7 13.Qf2 Nd4 14.Bd1 h5 15.Ne2 Nf5 16.c3 Nb8 17.d4 cxd4 18.cxd4 Nc6 19.Be3 Nb4 20.Qg1 Rc8 21.Bf2 Nd3 22.g3 Qa5 23.Kg2 Qd2 24.Rb1 Nxf2 25.Rxf2 Qd3 26.Rf3 Qd2 27.Ba4+ b5 28.Bd1 g5 29.Qf2 g4 30.hxg4 hxg4 31.Rb3 Bd8 32.Rc3 Rxc3 33.bxc3 Ne3+ {0-1, Ezio Righi 2116 - Peter Long 2302, Olympiad-39, Khanty-Mansiysk (6.3), 2010.09.27} ) 7...Nbd7 {a noncommittal developing move, prompting White to play the obvious next move to occupy the center and free the Bc1.} ( 7...Bc5 $5 {is the next most popular and scores slightly better in the database. The point of course is to prevent d4.} ) 8.d4 dxe4 {Black needs to exchange in the center, otherwise White's presence becomes too strong.} 9.Nxe4 Nxe4 10.Qxe4 Nf6 11.Qd3 {the situation in the center is now more resolved, with a standard Caro-Kann pawn structure for both sides and White having the two bishops, a slight long-term advantage.} 11...Qc7 {the queen move is logical, since it occupies the h2-b8 diagonal and at least temporarily prevents White developing with Bf4. However, it may be a premature commitment of Black's strongest piece.} ( 11...Be7 {is most played here, as the logical square for the bishop and to immediately prepare kingside castling.} ) 12.Rd1 {the best file for the rook, supporting the d-pawn again and therefore allowing the Qd3 more flexibility.} 12...Be7 13.a4 {a recently tried move, this indicates White intends to focus her attantion on the queenside. The easiest and best response appears to be simply to block further progress of the a-pawn and restrain the White b-pawn's advance.} 13...a5 14.Bd2 {it is not easy for White to find a good square for this bishop and it is awkwardly transferred here to e1.} 14...O-O 15.Be1 Rfd8 {Black logically places her rook on the best file, opposing White's pieces. The game is equal.} 16.Qc4 {neither side has obvious weaknesses to target, so the middlegame will necessarily feature some maneuvering. Black's plan is easier to identify, however: doubling rooks on the d-file and threatening a pawn break to open it up. The text move is not bad for White, but it does put the queen in the way of the c-pawn.} 16...Rd7 17.Bf3 {the bishop was not doing much on the other diagonal, so f3 is a better square for it.} 17...Rad8 18.c3 {logically reinforcing d4. Also, White has little better.} 18...e5 {Nimzovich famously wrote "the threat is stronger than the execution" - which seems true here. Black is fine after the resulting exchanges, but could have maintained the tension.} 19.dxe5 Qxe5 20.Qe2 Qxe2 21.Bxe2 Nd5 {having previously opted for exchanges, now Black chooses to wait and maneuvers the bishop to f6. It's not clear if this is better, however.} ( 21...Rxd1 22.Rxd1 Rxd1 23.Bxd1 Kf8 $10 ) 22.g3 {controlling the f4 square.} 22...Bf6 {this restrains the advance of White's b-pawn, but gives up its mobility along the f8-a3 diagonal and leaves the bishop biting on the c3 pawn.} 23.Bf3 {returning to its previous square, but now it appears less effective.} ( 23.Bg4 $5 ) 23...Nb6 {now we get another exchange in any case.} 24.Rxd7 Nxd7 {this is better because the knight goes to a better square afterwards.} 25.Ra2 {this appears to be a waiting move, to see what Black will do.} 25...Ne5 26.Be2 Nd3 {forcing the minor piece exchange. White can choose which bishop, however.} 27.Bxd3 Rxd3 28.Ra3 {from this point the position is very balanced, with near- symmetrical pawn structures. Black has better piece activity, but there is no way to make real progress.} ( 28.Ra1 $5 ) 28...Be7 29.Ra1 f5 {contesting g4 and opening the diagonal for Black's king to more quickly head toward the center.} 30.Kf1 {White moves to centralize her king as well, one of the most fundamental endgame principles.} 30...Kf7 31.Ke2 Rd7 32.b4 {White chooses to simplify things on the queenside.} 32...axb4 33.cxb4 Bf6 34.Rc1 Rd5 {defending against the idea of a White pawn advance on the queenside.} 35.a5 Re5+ 36.Kf1 {White can penetrate with the king, but cannot do any damage thereby.} ( 36.Kd3 Rd5+ 37.Kc4 Rd4+ 38.Kc5 Rd5+ 39.Kb6 Rb5+ $10 ) 36...Rb5 37.a6 {the series of exchanges that result mean the position will be drawn.} 37...bxa6 38.Rxc6 Be7 39.Rxa6 Bxb4 40.Bxb4 Rxb4 {short of a blunder, there is no possible result other than a draw at this point.} 41.Ke2 Rb3 42.h4 h5 43.Kf1 g6 44.Kg2 Rc3 45.Rb6 Rd3 46.Ra6 Rc3 47.Rb6 Rd3 48.Ra6 Rc3 1/2-1/2

08 January 2023

Book completed - The Fabulous Budapest Gambit (New Edition)

The "New and Updated" (2017) edition of The Fabulous Budapest Gambit by GM Viktor Moskalenko, which I recently completed, was probably the first openings book I studied more for general chess skills benefit rather than as a deliberate addition to my openings repertoire. That said, I probably will put the knowledge to use at some point and it seems like a very interesting and at times fun opening to play.

Table of Contents (from New in Chess site)

Moskalenko (as can be seen above) enjoys using some more creative, thematic and even poetic ways of classifying concepts and variations. This translates into (after 1. d4 Nf6 2. c4 e5 3. dxe5 Ng4):
  • Chapter 1: 4. Bf4 (Rubinstein Variation)
  • Chapter 2: 4. e4 (Alekhine System)
  • Chapter 3: 4. Nf3
  • Chapter 4: 4. e3 and sidelines, including the gambit declined
  • Chapter 5: The Fajarowicz Gambit (3...Ne4)

The primary reasons I went through this book, first using a physical board for initial study then entering chosen lines into my repertoire database, were to get exposed to new and different ideas, along with an appreciation and enjoyment of Moskalenko's teaching style. He starts and ends each chapter and sub-part with a discussion of key ideas for both sides, annotating a selection of complete games as showcases. These include everything from classic games by early 20th century giants up to contemporary tournament and internet games. 

While Moskalenko makes judgments about each line, it is deliberately not a fixed repertoire book and he encourages exploring different approaches and ideas. In that sense it is also a very practical book, not simply searching for the best theoretical line. At the same time, he does not flinch from pointing out serious difficulties and issues. The fact that he has real experience playing the opening at the tournament level is reflected in his ability to evaluate the practical chances in various lines and also present the opening as more of a living, breathing complex of ideas rather than a stale academic study.

It is important to evolve your openings repertoire over time, so that it (and you as a player) do not become stale and bored. For success in tournament play, it is also important to have more unbalanced openings in your toolkit, to be able to increase your winning chances in key situations. The surprise factor is also no joke, especially if your particular opening choice does well against "standard" or "obvious" moves played by an opponent unfamiliar with it. The Budapest Gambit appears to meet that need against 1. d4, as tactics lurk throughout it and in most lines it offers Black significant attacking chances. That said, there is still no "free lunch" and if your opponent plays solidly, as in most games of chess it will end up being your knowledge of the resulting middlegames and how to play them that determines how well you do against them.

27 December 2022

Commentary: U.S. Women's Championship 2022, Round 3 (Cervantes - Lee)

This round 3 game features a Slow Slav, which as the name implies normally does not have a lot of fireworks. However, close study reveals a game more like a stand-up boxing match, where each side jabs repeatedly at the other and looks for small openings. At first it seems that Black wants to keep the position more imbalanced to seek winning chances, then White does the same. However, White overreaches and Black had one opportunity on move 26 to win material and significantly imbalance things. After that the game heads for a draw, although the dynamic balance and a need by both sides to watch their weak points is what causes it, rather than a stagnant position.

[Event "U.S. Women's Chess Championship 2022"] [Site "Chess.com"] [Date "2022.10.07"] [Round "03"] [White "Cervantes Landeiro, Thalia"] [Black "Lee, Alice"] [Result "1/2-1/2"] [WhiteElo "2272"] [BlackElo "2263"] [ECO "D12"] [Annotator "ChessAdmin/Komodo 2.6.1"] [TimeControl "5400+30"] 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.e3 {the "Slow Slav"} 4...Bf5 5.Nc3 e6 6.Nh4 Be4 {the point is to provoke White's next and make the Nh4 placement more awkward.} 7.f3 Bg6 8.Qb3 {a common theme in the Slav, White takes advantage of the Black light-square bishop's early development by targeting b7.} 8...Qc7 {this has generally replaced ...Qb6 as standard. In top level master games White was consistently able to obtain a small plus and grind it after Nxg6. For Class players, it probably doesn't matter.} 9.Bd2 Be7 10.O-O-O {this is the first big decision for White in the line, determining the middlegame's characteristic. Here White decides to castle long, since the kingside is not in such great shape and it makes for a more dynamic game with opposite-side castling.} 10...dxc4 {releasing the central tension and the most played option here for Black.} ( 10...a6 $6 11.c5 $16 {and now the queenside is locked up with White's king safer.} ) ( 10...O-O {looks like a normal move but is rarely played. It makes it relatively easy for White to play against in the middlegame, using kingside pawn thrusts.} ) 11.Bxc4 a6 {the database and engines show equal results for Black at this point. With the d/c pawns exchanged, White lacks any near-term pawn levers and Black has a solid and harmonious position.} 12.Nxg6 {clearly a better trade for White, given the knight has so few squares.} 12...hxg6 {however Black remains very solid and still has not committed to castling, so the h-file is covered by the rook.} 13.Ne4 b5 ( 13...Nxe4 {is probably a quicker way toward a draw.} ) 14.Be2 Nbd7 {again Black avoids simplification with an exchange on e4. White's knight is relatively better there, so perhaps Black was still looking to eventually play for a win rather than head for a draw.} 15.Kb1 {this is almost always a useful move with a queenside-castled king, covering a2 - although here the Qb3 does that as well - and clearing c1 for a rook in the future.} 15...Rc8 {lining up behind Black's c-pawn lever.} 16.Be1 {apparently an original idea, as there are no games in my database. The repositioning of the bishop to g3 is logical, but does not cause Black any problems, and here she just proceeds with her c-pawn lever plan.} ( 16.Nxf6+ Nxf6 17.g3 $10 ) 16...c5 17.Bg3 Qc6 {it is difficult to know exactly where to put the queen in these kinds of positions.} ( 17...Qb6 $5 {would keep the queen off the c-file and potentially pressure e3.} ) 18.Nxc5 Nxc5 19.dxc5 Bxc5 20.Be5 ( 20.Rc1 {seems more to the point, although Black can simply castle and then play ...Qb7 to break the pin.} ) 20...O-O {Black would welcome an exchange on f6, giving Black control over e5, space for the king on g7, and elminating White's better bishop.} 21.h4 {sometimes White can take advantage of this type of pawn structure by using the doubled g-pawn as a target. However, this is not one of those times.} 21...Rfd8 {now Black is apparently happy with getting material off the board.} 22.Rxd8+ Rxd8 23.Rc1 ( 23.Qc2 $5 ) 23...Rd5 {Black's rook is now quite effective on the d-file, provoking the piece exchange.} 24.Bxf6 gxf6 {Black now has a small space advantage and White has no real prospects for making progress.} 25.Qc3 Qd7 26.h5 $6 {White now evidently wants to avoid heading for a draw, but creating this imbalance in the position would allow Black to do something similar on the queenside and with better effect. However, Lee continues with solid play, protecting the f6 pawn instead of counterattacking.} ( 26.e4 Rd2 27.Qxc5 Rxe2 28.Qc8+ Qxc8 29.Rxc8+ Kg7 30.Rc2 $10 ) 26...Be7 ( 26...b4 {the engine spots this opportunity.} 27.Qxf6 $2 Bxe3 28.hxg6 {this is not as scary as it looks and Black can win material.} 28...Bxc1 {and now White has nothing better than} 29.Kxc1 Rc5+ 30.Kb1 a5 {consolidating the queenside. Now Black's king could be subjected to a number of checks, but no real attack after} 31.g4 fxg6 32.Qxg6+ Kf8 $19 ) 27.hxg6 {the moment of imbalance passes.} 27...fxg6 28.f4 Rc5 29.Qb3 Rxc1+ 30.Kxc1 Qc6+ {with more material off the board and no breakthroughs possible without a blunder, the game now heads for a draw. Black will try to target the b- and e- pawns on dark squares, but White finds a dynamic counter.} 31.Kd1 Qe4 32.Bf3 Qb1+ 33.Ke2 Kf7 34.a3 f5 {fixing the White e-pawn.} 35.g4 Bf6 {targeting b2, but White can counter with} 36.gxf5 gxf5 37.Bh5+ {and Black's king position is too exposed to get away from the checks, since the e6 pawn has to be protected.} 37...Ke7 38.Qb4+ Kd7 39.Qd2+ Ke7 40.Qb4+ Kd7 41.Qd2+ Ke7 42.Qb4+ 1/2-1/2

Evaluation generated by HIARCS Chess Explorer Pro

26 November 2022

Commentary: U.S. Women's Championship 2022, Round 2 (Krush - Foisor)

This commentary game directly follows Eswaran - Lee from round 1 of the U.S. Women's Championship. I find it particularly valuable to look at similar but divergent games - this one again features an English with an e3/Be2 and b3/Bb2 structure against Black's Semi-Slav type setup. Black is the first to diverge from the previous game, pursuing a more assertive central strategy while White deliberately hangs back and waits to see if Black will over-commit. The conflicting central positional strategies merit close study, particularly the decisions around moves 16-20, as well as the clash of minor pieces and their exchanges. White ends up with the two bishops and eventually what could/should be a won ending, but the "all rook endings are drawn" saying again proves itself valid.

[Event "U.S. Women's Chess Championship 2022"] [Site "Chess.com"] [Date "2022.10.05"] [Round "02"] [White "Krush, Irina"] [Black "Foisor, Sabina-Francesca"] [Result "1/2-1/2"] [WhiteElo "2432"] [BlackElo "2203"] [ECO "A11"] [Annotator "ChessAdmin/Dragon by Komodo 2.6.1"] [TimeControl "5400+30"] 1.c4 c6 2.Nf3 d5 3.e3 Nf6 4.Nc3 e6 5.b3 Bd6 {the first deviation from Eswaran-Lee. Black is going to play differently, emphasizing controlling and occupying the e5 square.} 6.Bb2 O-O 7.Be2 {White's setup so far is standard in this line.} 7...e5 {this forces White into making a defining choice about the center.} 8.cxd5 {the principled exchange, also played in the vast majority of database games. The point of flank play is to create a target in the center that can be attacked/undermined, and exchanging off a supporting pawn advances that goal.} 8...cxd5 9.Nb5 {universally played here. Black's bishop is significantly better than White's knight in general, and is supporting the key e5 pawn, so exchanging it makes strategic sense.} 9...Nc6 {choosing to maintain the pawn on e5.} 10.Nxd6 Qxd6 11.O-O {this postpones any decision-making regarding the center.} ( 11.d4 {is standard here. White takes care not to give Black too much presence in the center and also forces Black to define intentions in the center.} 11...e4 12.Ne5 {and White is fine, as} 12...Qb4+ $6 13.Qd2 {just helps White develop, since the king would be quite safe on d2 after an exchange.} ) 11...Bg4 {this seems to be played without a specific purpose other than development, since there is no resulting pin on the Nf3 and Black then wastes time by not exchanging the minor pieces immediately.} ( 11...Bf5 $5 ) 12.h3 Bh5 13.d3 {Krush seems to be intentionally baiting her opponent by using a more passive strategy, seeing if Black will commit to something erroneous.} ( 13.Nd4 $5 {is an interesting solution to the placement of the Nf3, made possible tactically by the Q+B battery against the Bh5.} 13...Bxe2 14.Nxe2 {and now White has the option of f2-f4, while the knight helps control d4 and has c3 potentially to go to.} ) ( 13.d4 {is still possible as well.} ) 13...Rfe8 14.Rc1 ( 14.a3 {would result in a full Hedgehog-type pawn structure, which White however avoids. Here the b4 square is not so useful for Black.} ) 14...Rad8 15.Qd2 {developing the queen and connecting the rooks, while waiting to see what her opponent chooses to do.} 15...Bxf3 {perhaps Black got tired of trying to figure out what to do with her light-square bishop?} 16.Bxf3 e4 $6 {this is too committal, since the advance does not lead to an advantage. A waiting move like ...h6 would be useful, as an alternative.} 17.Be2 {White continues with her non-committal strategy.} ( 17.dxe4 {is recommended by the engine.} 17...dxe4 {often a supported, advanced e-pawn is a strength, but here the advance would open up the game for White after piece exchanges.} ( 17...Nxe4 {also would give White easy play in the center and an advantage with the two bishops.} 18.Qc2 Nb4 19.Qd1 Nxa2 20.Ra1 Nb4 21.Rxa7 $16 ) 18.Qxd6 Rxd6 19.Rfd1 {and White's bishops and rooks combine for an advantage. For example} 19...Red8 20.Rxd6 Rxd6 21.Bd1 Rd2 22.Bc2 $16 {and now if} 22...Nb4 $2 23.Bxe4 $18 {wins due to Black's back rank weakness.} ) 17...d4 {Black bravely (and correctly) presses forward, with all her pieces supporting the advanced pawns. Now the center will have to be resolved.} 18.Rcd1 dxe3 {Black leverages her pressure along the d-file.} 19.fxe3 ( 19.Qxe3 $6 Nd5 20.Qg5 f6 21.Qg4 e3 {and White is on the defensive.} ) 19...exd3 20.Bxd3 {White has the two bishops in an open position, but the isolated e-pawn offers Black a target as compensation.} 20...Ne4 {the knight looks good on the advanced central square, but this is premature. The queen sidesteps effectively to e2 and Black has no real threats. Moving the Black queen off the d-file instead would helpfully pin the bishop, for example with ...Qe7.} 21.Qe2 Qe7 ( 21...Qg6 22.Rf4 $16 ) 22.Rf4 {unlike in the above variation, this is less effective without another good target for the rook besides the Ne4. Qh5 or Qg4 seem more effective continuations, targeting h7 or g7 respectively.} 22...Ng5 23.Rdf1 {a pawn sacrifice that doesn't seem to offer much for White, other than trading material.} 23...Qxe3+ 24.Qxe3 Rxe3 25.Bc4 Ne5 26.Bxe5 Rxe5 27.Bxf7+ Nxf7 28.Rxf7 Rb5 {awkward-looking but an effective defensive move. In a double-rook ending with symmetrical pawns, a draw is normal unless one player blunder. Krush decides to try to press for a win, however.} 29.Rc7 a5 ( 29...h6 $5 {would get the h-pawn out of the line of fire of the rooks on the 7th rank and give the king a square on h7.} 30.Rff7 Rd1+ 31.Kh2 Rg5 {and now} 32.Rxb7 $2 Rd2 $17 {and the more important g-pawn goes.} ) 30.Rff7 Rd1+ 31.Kh2 Rg5 32.Rf2 h5 ( 32...h6 {would perhaps be more prudent.} ) 33.Rxb7 {still not decisive for White.} 33...Kh7 34.Rc7 Re5 ( 34...a4 $5 {with the idea of} 35.bxa4 ( 35.b4 Rb1 $10 ) 35...Rd4 36.Ra7 Rd3 {and the doubled rook pawns should be too weak to promote.} ) 35.Rff7 Rg5 36.Rc2 Kh6 37.Rfc7 Rdd5 38.R7c4 Rge5 {White of course has an edge, but with the double rooks and Black able to cover her weaknesses, there is no clear winning path.} 39.h4 Rb5 {this limits the scope of the Black rook, normally something to be avoided in rook endings.} 40.Rc6+ Kh7 41.R2c3 Re2 {Black's rooks are now uncoordinated and White tries to take advantage of this.} 42.a4 Rb4 43.R6c4 Re4 $2 {this simplifiies down and leaves Black's remaining rook out of position.} ( 43...Rb2 {rooks belong behind your opponent's pawns in an ending. This would also simplify, but with Black's remaining rook in a much better position.} 44.Rxb4 axb4 {and White's advantage is minimal.} ) 44.Rxe4 Rxe4 45.Rc5 {effectively swapping the White h-pawn for the Black a-pawn and giving White two connected passed pawns, which should be enough to win.} 45...Rxh4+ 46.Kg1 Kh6 47.Rxa5 $18 Rd4 {"all rook endings are drawn" is still a rallying cry for the worse-off player. Let's see how Black manages to draw here.} 48.Rb5 h4 49.a5 Rd1+ 50.Kf2 ( 50.Kh2 $5 ) 50...Ra1 51.Kf3 ( 51.Rb6+ {followed by a5-a6 looks more to the point.} ) 51...Ra2 52.b4 {this makes the situation too static. White's rook is out of place in front of her pawns, while Black's is behind them and also targets White's king and pawn from the side.} ( 52.Kg4 {White can use her king actively here.} 52...Rxg2+ 53.Kxh4 g5+ 54.Kh3 Ra2 55.Kg4 Rg2+ 56.Kf3 Ra2 ) 52...g5 {the engine considers the position with just a small advantage to White.} 53.Rb8 Ra3+ {over-using the rook and leaving the king passive.} ( 53...Kg6 ) 54.Ke4 ( 54.Kg4 Rg3+ 55.Kf5 Rxg2 56.b5 {and White will eventually win the pawn race, with Black running out of checks.} ) 54...Ra2 55.Rb6+ {this drives the Black king forward, where it wants to be. The engine shows that keeping the White king active and centralized is the key.} ( 55.Kf5 ) ( 55.Kd3 ) ( 55.Ke3 ) 55...Kh5 56.a6 Rxg2 {now the balance is more obvious. Both rooks can get behind the other side's pawns, but can't support their own to queen.} 57.Rb5 h3 58.a7 ( 58.Ra5 $2 h2 59.a7 h1=Q 60.a8=Q Ra2+ $19 ) 58...Ra2 59.Rb7 Kg4 60.b5 h2 61.Rh7 Rxa7 62.Rxh2 {now it is a forced draw.} 62...Ra4+ 63.Kd5 Rb4 64.Kc5 Rb1 65.Rc2 Kf3 66.Rc3+ Kf4 67.Rc4+ Kf3 68.Rc3+ Kf4 69.Rc4+ Kf3 70.Rc3+ Kf4 1/2-1/2

Evaluation generated by HIARCS Chess Explorer Pro

20 November 2022

Ronaldo v Messi: "[Chess] Victory is a state of mind"

As highlighted at Chess.com, there's a new Louis Vuitton campaign featuring Cristiano Ronaldo and Lionel Messi playing chess, with the tag line "Victory is a state of mind". Aside from the positive exposure for chess, it's good to see that they have a correctly set up board, featuring a position from a real game (Carlsen - Nakamura, Norway Chess 2017). As mentioned in "Chess imagery in popular culture" this is unfortunately rather rare; my favorite from that remains the Avengers headquarters with a colors-reversed chessboard.