Keene Defense

The Keene Defense, also called Keene's Defense, starts with the premature 2...Qh4+, which the parent entry warns against. After 3. g3 the queen has nothing better than to retreat, and 3...Qe7 puts it where it guards e5 and watches the e-file. The justification is that g3 has loosened White's kingside, especially the long light diagonal toward h1, so any later opening of the e-file can expose e4 and the white king. The cost is a queen developed early to a square that blocks the f8-bishop, plus lost time. Reference sources describe the line as dubious, and the engine gives White a slight edge.

The usual reply is 4. Nf3, a developing move that attacks e5. Next most common is 4. fxe5, which gives up the f-pawn's tension so the queen recaptures in the center. The third choice is 4. f5, which gains space and locks the kingside, though Black scores comparatively well against it. Engines prefer quiet development with 4. Nc3, 4. d3 or 4. c4. The line is an occasional sideline, mostly seen in online play, and results there are fairly close.