[%c_effect c5;square;c5;type;GreatFind;persistent;true] The only way to justify Black's previous move. This must be accurately calculated or prepared.
1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... f8b4  4. g1f3  4... d7d6  5. d1c2  5... e8g8  6. c1d2  6... b7b6 [%c_effect b6;square;b6;type;GreatFind;persistent;true] A good and provocative move, allowing White to advance the pawn to e4. 7. e2e4 