Gambit. This gambit was named by Alexander Wagner (1868–1942), a Polish chess player and openings analyst who introduced it in the Swiss correspondence game Wagner–Kostin, 1910–11. The term "Swiss Gambit" is often used to refer more generally to 1.f4 f5 2.e4. Chess historian Edward Winter has criticized that usage, pointing out that 1.f4 f5 2.e4 was analysed by F.A. Lange in the June 1859 Deutsche Schachzeitung, and was played by many players, including Adolf Anderssen, in the nineteenth century. An aggressive but rare response is 1...g5?!, the Hobbs Gambit, with play possibly continuing 2.fxg5 h6, a sort of mirror image Benko Gambit. White can simply return the pawn with 3.g6, leaving Black with a weakened after 3...fxg6. A variant is the Hobbs–Zilbermints Gambit, 1...h6 intending 2...g5; against this, White could proceed with 2.e4 g5 3.d4, when Black has lost time and weakened their kingside. Another offbeat try is Martin Appleberry's 1...Nh6!?, also known as the Horsefly, which exploits the closed c1-h6 diagonal. One idea is to meet 2.b3 with 2...e5, another deferred From Gambit, and 2.e4 with 2...d5, when 3.exd5 Qxd5 would result in a Scandinavian Defense where White's pawn is oddly placed on f4. However, 2.Nf3 avoids both of these lines. The primary objective of the Horsefly is to retain control of e5, preventing the Stonewall attack, but otherwise giving White great flexibility. Another possible reply by Black is 1...Nc6. With this move, Black lays the support for the advance of the e-pawn. The general sequence of moves that Black may opt for is ...g6, ...Bg7 and ...d6 and eventually advance the e-pawn. Another possible reply is 1...e6. This exploits the weakness created by 1.f4 on the e1–h4 diagonal by releasing the queen, and also releases the without offering a pawn, unlike the From Gambit. White should avoid playing 2.g4?? as it leads to 2...Qh4# (a variation of the Fool's Mate). 2.e4 transposes to the La Bourdonnais Variation of the French Defense (the normal order being 1.e4 e6 2.f4). Popularity Out of the twenty possible opening moves, 1.f4 ranks sixth in popularity in Chessgames.com's database, behind 1.e4, 1.d4, 1.Nf3, 1.c4, and 1.g3. It is less than one-twentieth as popular as the mirror image English Opening (1.c4). The move 1.f4 slightly weakens White's king's position. Chessgames.com's statistics indicate that the opening is not an effective way of preserving White's first-move advantage: as of February 2013, out of 3,872 games with