Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...Nf6/4. O-O/4...Ng4

Black's knight forays into White's territory. This leads to a trap where Black baits White into opening the h-file.

After 5. h3 h5 sets a trap: the bait is the g4 knight, the h3 pawn is the fish, and the h5 pawn is the hook. Black appears to blunder his knight, but 6. hxg4?? hxg4 opens the h-file onto White's castled king, and attacks the f3 knight. Trying to save the knight leads to forced mate, 7. Nh2?? Qh4!. White's best recourse is to allow the knight to be captured.

White can sidestep the trap by leaving Black's knight on g4 and continuing to develop normally: 6. c3 intending d4, 6. d4, 6. Nc3 are all playable and leave White with the advantage.

The same trap can arise out of the Morphy defence, after 3...a6 4. Ba4 Nf6 5. O-O Ng4.

For explanation of theory tables, see theory table and for notation, see algebraic notation..

1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.O-O Ng4

When contributing to this Wikibook, please follow the Conventions for organization.

Wikipedia has related information at Fishing Pole (chess).