1. e2e4  1... e7e5  2. f1c4 The Bishop Variation is normally used to avoid the Petroff, which has proven to be a difficult defense to break, just look at Nepomniachtchi's games. I believe Wei was not so familiar with its nuances, as he will quickly be out of the book. 2... g8f6  3. d2d3  3... f8c5 3...Nc6 and 3...c6 are also very popular. 4. b1c3  4... c7c6 Wei said he was surprised by this move. It has been played, however, in hundreds of games, including games by super-grandmasters. 5. f2f4 A brave choice for someone who doesn't know theory. 5... d7d5 Warmerdam took his time before playing this move. It's likely that he was also out of book here, or at least did not do much analysis of this position. 6. e4d5  6... f6g4 This move brings chaos to the board. Black has many options. 7. g1f3 White thought for 50 minutes to play this move. 7... e8g8  8. f4e5  8... g4f2  9. d1e2  9... f2h1  10. c1g5 [%c_effect g5;square;g5;type;GreatFind;persistent;true] Developing the bishop and attacking the queen. It's surprising, but I found three correspondence games in this position. 10... d8a5 The only acceptable square for the queen. 11. d5d6 [%c_effect d6;square;d6;type;GreatFind;persistent;true] Opening the bishop's diagonal and keeping a dangerous passed pawn on the sixth rank. At this point, the three correspondence games deviate: each had a different move. 11... c8g4  12. g5e7  12... b8d7 [%c_effect d7;square;d7;type;Inaccuracy;persistent;true] 13. e5e6  13... c5a3 [%c_effect a3;square;a3;type;GreatFind;persistent;true] Warmerdam finds the important resource, but the position is even more difficult to play now. 14. e6f7  14... g8h8  15. e1c1  15... a5c3  16. b2a3 The climax of the game. It's simply impossible to find the best move for Black in this position. 16... g4f3 [%c_effect f3;square;f3;type;Mistake;persistent;true] Correctly pointed out by Wei as the decisive mistake. 17. g2f3 The exchange of the bishop for the knight made life much easier for White. The h1-knight will finally be captured, and White will have an overwhelming advantage. 17... d7e5  18. c1b1 [%c_effect b1;square;b1;type;GreatFind;persistent;true] 18... c3d4  19. d1h1  19... e5c4  20. d3c4  20... d4b6  21. b1c1 