1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. g1f3  3... f8b4  4. c1d2  4... c7c5 [%c_effect c5;square;c5;type;Interesting;persistent;true] This is an interesting variation of the Bogo-Indian Defense, a favorite of the legendary GM Viktor Korchnoi. I played this move many times during my career, but I must admit that my results were not as good as Korchnoi's and Nakamura's, which is not so surprising, to be honest. 5. d2b4  5... c5b4 It seems strange that Black accepts to keep doubled pawns. After all, isn't this a weakness from a strategic point of view $2 I believe that \"doubled pawns\" is one of the most misunderstood topics in chess, but this philosophical conversation needs to be continued on another occasion. As compensation, the pawn on b4 causes some discomfort in White's position, gaining space and restricting his play on the queenside. It's not surprising that in many cases White plays a2-a3 at some point, voluntarily giving up this so-called strategic advantage. 6. g2g3  6... b7b6  7. f1g2  7... c8b7  8. e1g1  8... a7a5  9. d1d3 [%c_effect d3;square;d3;type;Interesting;persistent;true] A natural plan, intending to bring the knight to d2 and then playing e2-e4. 9... e8g8  10. b1d2  10... d7d6  11. e2e4  11... e6e5 [%c_effect e5;square;e5;type;GreatFind;persistent;true] Black needs to fight for the center. 12. a2a3 This move is probably not the most accurate.