This week's featured game was played at the Chigorin Memorial Tournament a few years ago. Mikhail Chigorin (1850-1908) is probably the most under-recognized player in chess history. The founder of the Russian school of chess, he was the challenger for the world championship in 1889 and 1892 but never won.
Chigorin's Defense (1.d4 d5 2.c4 Nc6) has achieved respectable results in top play around the world. Black tends to achieve quick development and piece pressure. These advantages force white to play very carefully, and if not prepared, often passively leading to a slight edge for black.
The opening we see in this game between Kachar and Kochyev is the King's Indian Defense (KID). One of the hypermodern openings players develop on the flanks first and then challenge the opponent's central control the KID is employed by many grandmasters today, including GM Gary Kasparov.
The kind of attack that black gets in this game is typical of this opening. Notice how quickly Kochyev gets in the driver's seat and calmly builds his attack until it is time to break through Kachar's position with 27...g4!
Kochyev then uses the activity of his pieces to create the winning combination. Piece activity is a goal in chess that I cannot stress enough. You can solve tactical puzzles until your eyes glaze over, but it will do you no good unless you can create such opportunities in a game. The only way to go about doing that is to make your pieces more powerful than your opponent's.