[%c_effect c5;square;c5;type;GreatFind;persistent;true]
1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. g1f3  3... d7d5  4. g2g3  4... d5c4  5. f1g2  5... c7c6 Only the sixth most popular move, but even so, it still has more than a thousand games played. The Catalan is a huge opening. 6. f3e5  6... f8b4  7. c1d2  7... b4e7 [%c_effect e7;square;e7;type;GreatFind;persistent;true] 8. e2e3 Protecting the d4-pawn before capturing on c4. 8... e8g8  9. e5c4  9... b7b6  10. e1g1  10... c8b7  11. d1b3 [%c_effect b3;square;b3;type;Mistake;persistent;true] This makes things too easy for Black, since now it's difficult to prevent the liberating c6-c5. 11... d8c8 [%c_effect c8;square;c8;type;GreatFind;persistent;true] Protecting the bishop and preparing c6-c5. 12. e3e4 Trying to create some activity in the center, but this make things worse.