1.e4 e5 2.f4 exf4 3.Nf3 Nf6 The Schallop Defence which is one of the more uncommon Black variations of the Kings Gambit Accepted. [More usual, apart from the critical and double-edged 3...g5, are the following moves. Some games from my own praxis show the kind of chances White gets in these variations especially if Black loses time in the opening. 3...d5 The Modern Defence 4.exd5 Nf6 (4...Qxd5 5.Nc3 Qd8 6.d4 Nf6 7.Bxf4 and White has a pleasant game recovering the pawn and with open lines still as in Donnelly-Rogers, Training game with clocks, Kenilworth 2017 which concluded 7...a6 8.Bd3 Bb4 9.0-0 Bxc3 10.bxc3 Nd5 11.Bd2 0-0 12.Bxh7+ winning a few moves later.) 5.Bc4 Qe7+ 6.Be2 Qc5 7.d4 Qxd5 8.0-0 Be7 9.Bxf4 Qd8 10.c4 0-0 11.Nc3 a6 12.Qc2 Bd6 13.Bg5 Be7 14.Rad1 Ng4 15.Bc1 c5 16.d5 Bd6 17.h3 Ne5 18.Ne4 Qc7 19.Nxd6 Nxf3+ 20.Rxf3 Qxd6 21.Bf4 Qb6+- Donnelly-Johnson, Coventry League 1998.; and 3...Be7 the Cunningham Defence 4.Bc4 d5 5.exd5 Nf6 6.Nc3 0-0 7.0-0 Bg4 8.d4 Bb4 9.Qd3 Bxc3 10.Qxc3 Ne4 11.Qb3 g5 12.Ne5 Bh5 13.Qxb7 Nd7 14.Nc6 Qf6 15.Qxc7+- Donnelly-Dobedoe, Training Match , Coventry 1990.]
4.e5 [The most direct line. Instead defending the e4 pawn with 4.Nc3 would allow Black the opportunity to transpose to the Modern variation via 4...d5 5.exd5 ]
4...Nh5 5.Qe2 Also a fairly uncommon move which provides for castling queens-side at the cost of a temporary prevention of development of the king's bishop. The move has been played by strong attacking players such as Keres and Junge. Far more usual are [5.d4 ,the most popular move in this position, and as analysed by CCIM Thomas Johansson in "The Kings Gambit for the Creative Aggressor". Although GM John Shaw in the Quality Chess book "The Kings Gambit" simply states (with no supporting analysis) Black can get a good game with 5...d6 . However, 6.Qe2 now looks to provide White with a decent game, for example, as played in high level event games such as Nimtz-Mraz, W-ch 18 corr ICCF 2003 and Fedorov-Yemelin, Tchigorin Memorial, St. Petersburg 1996. White winning both games.; Instead 5.Be2 ,the second most popular move here and with a veiled threat to the Nh5, is the line preferred by Shaw.]
5...Be7 [Alternatively 5...g5 is a common move in the Kings Gambit but other than defending the extra pawn this move does not have a lot to recommend it in this specific position. White can continue to open lines with the characteristic move 6.g4 and obtain good play for the pawns sacrificed after 6...fxg3 7.d4 Be7 8.Bh3 gxh2 9.Rxh2+/- as occurred in Merker-Baller, GER E-mail 1999.; 5...g6 is less weakening and gave Black a decent game after 6.d4 Be7 7.Nc3 and now the key freeing move in Open Games of 7...d5 (Less effective are 7...c6 8.g4 fxg3 9.Bh6 d5 10.exd6 Qxd6 11.0-0-0 Bg4 Stocek-Kirsanov, Monarch Assurance, Port Erin 2001.; and 7...Bh4+ 8.Nxh4 Qxh4+ 9.Qf2 Qxf2+ 10.Kxf2 c6 11.Ne4 Keres-Kruhzkops, Baltic Tm, Riga 1945. In both cases White has a good game.) 8.exd6 Qxd6 in Deutsch-Formanek,USA open Aspen 1968.]
6.d4 0-0 [6...Bh4+ is again shown as poor after 7.Kd1 0-0 8.g4 fxg3 9.Qg2 Baxter-Perrault, CCCA Canada 1959.]
7.Nc3 [A famous game went here 7.g4 fxg3 8.Nc3 d5 9.Bd2 Nc6 10.0-0-0 Bg4 11.Be3 f6 and Black had a good game in Keres-Alekhine, Salzburg 1942.]
7...d6 8.Bd2 dxe5 9.dxe5 Bh4+ Black is again tempted by this check but it proves futile in preventing White's aims. Better was simple development via [9...Be6 10.0-0-0 Nc6 11.g3 fxg3 12.hxg3 Bg4 13.Qe4 Qc8 14.Nd5 Malinin-Razvalyaev, URS-chT 10, Russia 1991.]
10.g3 Once more all the lines are opened at the cost of some pawns.
10...fxg3 [10...Nxg3 is a better version of taking on g3. 11.hxg3 Bxg3+ 12.Kd1 Bf5 Although Black obtains 3 pawns for the piece and displaces the White king, he still has the slightly worst game. White can untangle his pieces with Bh3/Kc1/Ne4 together with a4-a5/Ra4 and the open files towards Black's king have not gone away.]
11.0-0-0 Bd7 12.hxg3 White goes for it investing even more material to ensure the f-, g- and h-files are opened up. Steadier play with Bg2 then hxg3 was also possible but the move played is extremely difficut to defend against in a practical game.
12...Nxg3 13.Qh2 Nxh1 14.Nxh4 The Nh1 cannot escape so White has the guarantee of all least easily recovering some of the material. However, this is not a position where material counts. More important are time, pieces developed and open lines.
14...Bg4 15.Bd3 Cave-man play which pays off hansomely. White did not need to invest in yet more sacrifices since Black could have defended a lot better than he did. Strongest is simply [15.Be2 when White is so far ahead in development that Black cannot hold out very long. A few sample lines are 15...Qc8 (15...Bxe2 16.Nxe2 Nd7 17.Rxh1 Re8 18.Nf5 Nf8 19.Nxg7 Kxg7 20.Qh6+ Kg8 21.Bg5+- ) 16.Nd5 Kh8 17.Rxh1 Bxe2 18.Ng6+ and mate next move.]
15...Bxd1 Black grabs the material but loses in short order. Instead [15...Nf2 distracts White just enough to allow some sort of defence 16.Qxf2 Bxd1 17.Nxd1 Nc6 and Black is surviving. The game remains difficult for Black though, as despite the material advantage, White will follow with Nf3 and Ne3 and with options of Nf5/Ng5/Nd5 still gives White some kings-side pressure.]
16.Nf5 Qxd3 Trying to slow White down by removing the strong attacking bishop but its does not help. Efforts to develop demonstrate Black's problems: [16...Nc6 17.Ne7+ Nxe7 18.Qxh7# ; and 16...g6 forming a barricade against the Bd3 fails to 17.Qh6 gxf5 18.Bxf5 and h7 cannot be defended.]
17.cxd3 Bg4 18.Nh6+ Instigating a nice finish to force open Black's kings-side.
18...gxh6 [The knight must be taken as 18...Kh8 19.Nxg4 wins a piece and the knight on h1 also remains lost.]
19.Qxh6 Nd7 [19...f6 is also hopeless as the king is too open eg 20.exf6 Rf7 21.Qg5+ Kh8 22.Qxg4 Nc6 23.Ne4 Rg8 24.Ng5 Rxg5 25.Bxg5 with the threat of Qc8 and still of winning the knight on h1.]
20.Nd5 Rae8 [20...Kh8 only extends the game a whilst and allows White to prove the black squares are fatally weak, for instance, 21.Nf6 Nxf6 (21...Bf5 22.Nxd7 Rg8 23.Qf6+ Rg7 24.Bh6 Rag8 25.Bxg7+ Rxg7 26.Qxf5+- ) 22.Qxf6+ Kg8 23.Bh6 and mate next move.]
21.Nf6+ [After 21.Nf6+ Black resigned as there is no defence to mate eg 21...Nxf6 (21...Kh8 22.Qxh7# ) 22.exf6 and mate on g7 follows.] 1-0