London system is also more like a set-up than an opening line. White has a clear set-up in mind. 1.d4 d5 2.Nf3 Nf6 3.Bf4 c5 4.e3 Nc6 5.c3 e6 6.Nbd2 Be7 7.Bd3 0-0 8.0-0, and we get a set-up of the London system. White can play this almost against any response that black chooses.
White’s idea is to occupy the e5 square with knight and try to generate a very slow positional attack. In this post we will see a few lines to get a sense of how the game can be played.
Black plays 5…Qb6
Similar to the Torre attack and Trompowsky attack, black can attack the weak b2 pawn early in the opening. For example, in the above line black can play 5…Qb6
White can play 6.Qb3 or 6.Qc1. But not 6.Qc2 because of 6…Bf5! And black develops the bishop with tempo. White can’t take 7.Qxf5 because of 7…Qxb2 and a1 rook will be lost.
After 6.Qb3 Qxb6 7.axb6 gives white an open a file and the double pawn is not a weakness in this position. Black’s main move is 6…c4
Here, white can either take on b6. After 7.Qxb6 axb6 black’s double pawns are actually annoying because black will play b5-b4 to disrupt white’s strong pawn chain.
Better is to retreat with 7.Qc2. Black’s c4 move released pressure from the d4 pawn, therefore white’s queen achieved its objective and can return. After 7…Bf5 8.Qc1 h6 9.Nd2 e6 10.Be2 the game will develop naturally.
White’s d4 point is now very strong, but on the other hand white had to make three moves with his queen and c1 is not a great square for queen.
Instead of 6.Qb3, white can directly play 6.Qc1 and after 6…Bf5 7.Nbd2 e6 8.Be2 the position is similar to above variation but it is good for black because the pawn is still on c5, creating pressure on the d4 pawn.
Black plays early Qb6
Black can also play 4…Qb6, attacking the b2 pawn as early as possible.
But here, white can play 5.dxc5 Qxb2 6. Nbd2 Qc3 7.Bb5+ Nc6 8.0-0 and white has a good position. Black can easily get into trouble because his king is still in the center and white’s pieces are ready for attack.
Move like 8…Qxc5 is already a mistake here. After 9.c4 e6 10.Nb3 Qa3 11.Ne5 white gets a dangerous attack.
London system against 1…Nf6
After 1.d4 Nf6 white still plays London system, but black has more flexibility here. For example, after 2.Nf3 e6 3.Bf4 b6 4.e3 Bb7 5.Nbd2 Be7 6.h3 0-0 7.Bd3 c5 8.c3 Nc6 9.0-0 d6 10. Qe2 Re8,
We have London system against the Queen’s Indian set-up. The center is not fixed and both sides have flexibility. White can try to play e4-e5 or e4-d5. Black has possibility of playing either d5 or e5 with an interesting positional battle.
After 2.Nf3 g6 3.Bf4 Bg7 4.e3 d6 5.Bd3 0-0 6.0-0 c5 7.c3 Nc6, we have London system against the King’s Indian defense. Black is quite fine here, ready to play e5 and strike in the center.
White Plays Nc3
1.d4 d5 2.Bf4 Nf6 3.Nc3 is a variation of London system that white can play. It is basically based on a trap. For example after 3…c5 4.e3 and here the natural move 4…Nc6 is a blunder because of 5.Nb5 and white wins material because of Nc7+ threat.
But black can simply play 4…cxd4 5.exd4 a6 and black is fine. White’s knight on c3 looks a bit misplaced here.
Game Played with Trompowsky attack
Here is classic game played between Giri, Anish (2771) vs So, Wesley (2794)
Conclusion
London system is a very popular opening at all levels because it requires minimum effort in opening preparation and can get a playable position. If you are more inclined towards playing positional battles, this opening is good for you. But because white’s set-up is mostly the same, it doesn’t allow much flexibility for those who want to explore and practice variety of chess positions.