Chess Opening Theory/1. e4/1...e5

Open game C20–C99 King's pawn game 2. Nf3 - King’s Knight opening 2. Bc4 - Bishop's opening 2. f4 - King's gambit 2. Nc3 - Vienna game 2. d4 - Centre game 2. d3 - Leonardis variation 2. Qh5 - Parham attack 2. Qf3 - Napoleon attack 2. c3 - MacLeod attack 2. c4 - The Whale 2. Bb5 - Portugese opening 2. Ne2 - Alapin opening 2. Bd3 - Tortoise opening 2. a3 - Mengarini's opening 2. Nh3 - Basman attack 2. f3? - King's Head opening 2. Ke2?? - Bongcloud attack 2. b3 2. g3 2. g4 1...e5 · Open game 1...e5 is the Open game (or the Double King's Pawn game). It is Black's classical response to 1. e4. By mirroring White's move, Black grabs an equal share of the centre and scope to develop some pieces. 1...e5 is also one of the few moves that directly interferes with White's ideal plan of playing d4. But, the move's merit is also a drawback: the longer the position remains symmetrical, the longer White will have an advantage by moving first. Though the move is still common at every level, it saw a modest decline in popularity during the 20th century. Black's pawn on e5 is undefended, so it is easy for White to develop in a way that restricts Black's possible responses by threatening to capture it. This is White's most common plan, but they may also chose to develop without attacking. Attack the pawn White may attack Black's undefended e5 pawn. By attacking, White keeps the initiative: Black is forced to react to White's plans or they could lose the pawn. 2. Nf3 is the overwhelmingly popular move here, about ten times more common than everything else combined. This attacks the pawn while also developing a piece. Additionally, it controls the d4 square, ready to support a future d4 pawn push, and starts to make room for White to castle. By far Black's most common response is 2...Nc6, to defend the pawn while developing a piece. Alternatively, White can attack with a pawn. 2. f4, the King's gambit, confronts the e5 pawn and tries to lever open the f-file for an attack on Black's weak f7 pawn. This is the quintessential Romantic chess opening, popular with the likes of Paul Morphy and a staple of chess repertoires in the time when it was considered bad manners to decline a gambit. Its popularity began to wane in the late 19th century, but received some revival in the 20th century thanks to players including David Bronstein. A prepared Black player should be able to grab the proffered pawn and keep it. 2. d4, the centre game, smashes the centre open. White can then sacrifice a pawn or two to develop pieces with great speed (2...exd4 3. c3, the Danish gambit). 1. e4 e5 2. Nf3 King's knight opening 1. e4 e5 2. f4 King's gambit 1. e4 e5 2. d4 Centre game Develop a piece Since White's pieces are not under threat, they have the opportunity to choose which piece to develop. The main alternatives are 2. Bc4, the Bishop's opening, and 2. Nc3, the Vienna game. These don't immediately challenge e5 so Black has a little more flexibility in how they respond, but they are still solid moves and they keep open the option of either d4 or f4. Instead of their kingside knight, White can prioritise their queenside knight with 2. Nc3. Depending on Black's response and their preference, they may following with 3. f4 (the Vienna gambit, a souped-up King's gambit). If White would like to develop their bishop first, then its best move is 2. Bc4 (Be2 is very passive, Bd3 blocks in White's d pawn, Bb5 gets kicked by c6, and Ba6 bxa6, of course). The Bishop's opening is very transpositional depending on how Black responds. 1. e4 e5 2. Nc3 Vienna game 1. e4 e5 2. Bc4 Bishop's opening Playing for tricks There are many alternative moves, but all with drawbacks. Some of these are playing for tricks: 2. Qh5, called the Wayward Queen or Parham attack, and 2. Qf3 (called the Napoleon attack). White hopes Black will blunder in the face of unbridled aggression and allow them to "Scholar's Mate" them or drop material, and if it is Black's first day playing chess, they will succeed (e.g. 1. e4 e5 2. Qh5 g6?? 3. Qxe5+ Ne7 4. Qxh8). If Black keeps their head, these moves are not dangerous. 1. e4 e5 2. Qh5 Parham attack 1. e4 e5 2. Qf3 Napoleon attack Bad moves Some other moves are minor mistakes, where White is just a bit too passive and fails to develop: 2. d3?!, the Leonardis variation. A needlessly passive reply where White doesn't develop a piece and blocks in their bishop voluntarily. It resembles a Philidor defence in reverse. 2. c3?!, the MacLeod attack aka centre pawn opening. White prepares to push d4, then after exd4 cxd4 they end up with two pawns in the centre. However, this seldom works out as Black can play d5 first. 2. a3, 2. a4, and 2. h3 essentially function to pass the turn to Black with minimum disruption to White. Everything else is very bad. Some of these still have names (there is a lesson here: just because it has a name does not mean it's any good): 2. Bb5?, the so-called Portuguese opening. Unlike 1. e4 e5 2. Nf3 Nc6 3. Bb5, the bishop on b5 has nothing to do and can be kicked away by c6. We can only assume it is so named as a play on the Spanish game (i.e. Portuguese is a language that is superficially similar to Spanish). 2. Ne2?, Alapin's opening. The knight is misplaced here, preventing development of the bishop and queen. Perhaps White thinks to support either d4 or f4, but it is simply too slow and hands Black the initiative. 2. Nh3?, the Basman attack, is named after IM Michael Basman who played the move in a game in 2013. The knight lays little claim to the centre, but it can be used to avoid highly theoretical lines. 2. Ke2?, aka the Bongcloud, a deliberately bad "meme" opening used as a joke. An internet-famous game between Magnus Carlsen and Hikaru Nakamura drew by repetition after both players played Ke2 Ke7 Ke1 Ke8 repeatedly.Carlsen v Nakamura 2021 - Chessgames.com 1. e4 e5 2. d3 Leonardis variation 1. e4 e5 2. c3 Centre pawn opening 1. e4 e5 2. Bb5 Portuguese opening 1. e4 e5 2. Ne2 Alapin's opening 1. e4 e5 2. Nh3 Basman Attack 1. e4 e5 2. Ke2 Bongcloud Statistics Approximate chances White win 51%, Draw ??%, Black win 45%. Estimated next move popularity Nf3 82%, Bc4 5%, Nc3 4%, f4 4%, d4 2%, all others less than 1% Continuation frequencies in different databases move average 365Chess.com (big) Chess Tempo (all) chessgames.com Lichess (masters) Lichess (database) 2. Nf3 82.1% 86.0 87.3 84.7 91.7 61.1 2. Bc4 4.8 3.8 3.7 2.9 3.2 10.4 2. Nc3 4.4 4.2 4.1 4.8 2.7 6.2 2. f4 4.1 3.7 3.0 6.1 1.7 6.1 2. d4 2.3 1.7 1.5 1.1 0.6 6.4 2. d3 0.6 0.1 0.1 0.0 0.0 2.9 2. Qh5 0.6 0.1 0.0 0.0 0.0 2.9 2. Qf3 0.3 0.0 0.0 0.0 0.0 1.3 2. c3 0.2 0.0 0.0 0.0 0.0 0.6 2. c4 0.1 0.1 0.1 0.0 0.0 0.4 2. f3 0.1 0.0 0.0 0.0 0.0 0.4 2. g3 0.1 0.0 0.0 0.0 0.0 0.3 2. Bb5 0.1 0.1 0.0 0.0 0.0 0.2 2. Ne2 0.1 0.0 0.0 0.1 0.0 0.1 2. g4 0.0 0.0 0.0 0.0 0.0 0.0 2. Ke2 0.0 0.0 0.0 0.0 0.0 0.0 everything else 0.2 0.1 0.1 0.0 0.0 0.8 Theory table all 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Be7 6. Re1 b5 7. Bb3 d6 8. c3 O-O 9. h3 Na5 Spanish game,closed Spanish 2. ... ... 3. Bc4 Bc5 4. c3 Nf6 5. d3 d6 6. O-O a6 7. a4 Ba7 8. Re1 O-O Italian game,giuoco pianissimo 2. ... ... 3. d4 exd4 4. Nxd4 Nf6 5. Nxc6 bxc6 6. e5 Qe7 7. Qe2 Nd5 8. c4 Scotch game 2. ... ... 3. Nc3 Nf6 4. Bb5 Bb4 5. O-O O-O 6. d3 d6 7. Bg5 Bxc3 8. bxc3 Qe7 Four knights 2. ... ... 3. c3 d5 4. Qa4 f6 5. d3 Be6 6. Be2 Ne7 7. O-O Qd7 8. Nbd2 g5 Ponziani 2. ... Nf6 3. Nxe5 d6 4. Nf3 Nxe4 5. d4 d5 6. Bd3 Nc6 7. O-O Be7 8. c4 Nb4 Russian game,classical 2. ... d6 3. d4 exd4 4. Nxd4 Nf6 5. Nc3 Be7 6. Be2 O-O 7. O-O Re8 8. f4 Bf8 Philidor defence,exchange 2. Bc4 Nf6 3. d3 c6 4. Nf3 d5 5. Bb3 Bd6 6. Nc3 dxe4 7. Ng5 O-O 8. Ncxe4 Nxe4 Bishop's opening,Berlin defence 2. Nc3 Nf6 3. g3 d5 4. exd5 Nxd5 5. Bg2 Nxc3 6. bxc3 Bd6 7. Nf3 O-O 8. O-O Nc6 Vienna game,Mieses variation 2. f4 exf4 3. Nf3 g5 4. h4 g4 5. Ne5 Nf6 6. Bc4 d5 7. exd5 Bd6 8. d4 Nh5 King's gambit accepted,Kieseritzky gambit 2. d4 exd4 3. Qxd4 Nc6 4. Qe3 Nf6 5. Nc3 Bb4 6. Bd2 O-O 7. O-O-O Re8 8. Qg3 Rxe4 Centre game,Berger variation 2. ... ... 3. c3 dxc3 4. Bc4 cxb2 5. Bxb2 d5 6. Bxd5 Nf6 7. Bxf7+ Kxf7 8. Qxd8 Bb4+ Danish gambit accepted,Schlechter defence 2. d3 Nc6 3. Nf3 Nf6 4. Be2 d5 5. Nbd2 Bc5 6. O-O O-O 7. c3 a5 8. b3 Re8 Leonardis opening (transposing to Tayler opening) 2. Qh5 Nc6 3. Bc4 g6 4. Qf3 Nf6 5. Ne2 Bg7 6. d3 d6 7. h3 O-O 8. Nbc3 Parham attack 2. Qf3 Nc6 3. Bc4 Nf6 4. Ne2 d6 Napoleon attack 2. Bb5?! c6 3. Ba4 Nf6 4. Qe2 Bc5 Portuguese opening 2. c3!? d5 3. Nf3 Nf6 4. Nxe5 Bd6 MacLeod attack 2. c4!? Nf6 3. Nc3 Bc5 4. g3 d6 English, the whale(by transposition) 2. Ne2!? Nf6 3. Nbc3 Nc6 4. g3 Bc5 Alapin opening 2. a3!? Mengarini's opening 2. Bd3!? Tortoise 2. Ke2?? Bongcloud attack References Open Game Bibliography Panov, Vasily (1973). Teoría de Aperturas, Tomo I: Aperturas Abiertas - Aperturas Semiabiertas. 84-270-0132-0. Schiller, Eric (2002). Standard Chess Openings. 1-58042-048-6. External links 365Chess: 1. e4 e5 fi:Shakkiaapinen/Peli/1. e4/1...e5