Ryder Gambit

The Ryder Gambit arises when White recaptures on f3 with the queen rather than the knight. The queen no longer guards d4, so a second pawn is offered. It was the line Emil Josef Diemer analyzed most thoroughly in his book on the gambit. White aims for quick queenside castling, pressure along the f-file and against b7, and open lines for every piece. Accepting with 5...Qxd4 is the critical test, and the engine regards Black as clearly better after it. Gary Lane judged that White struggles to justify the material after 5...Qxd4 6. Be3 Qg4 7. Qf2 e5.

Greedy play carries risks. In the Halosar Trap, 5...Qxd4 6. Be3 Qb4 7. O-O-O Bg4? 8. Nb5 threatens Nxc7 mate, and the queen cannot take the knight because Bxb5 would come with check. Many players decline the second pawn instead. The most frequent reply is 5...e6, followed by 5...Nc6 and 5...c6. The developing 5...Bg4 scores badly for Black in practice. Despite the engine's verdict, White wins more often than Black in online games.