Gaining space on the queenside and removing the pawn from a potential capture by the opponent's queen.
1. c2c4  1... g8f6  2. b1c3  2... e7e5  3. g1f3  3... b8c6  4. g2g3  4... d7d5  5. c4d5  5... f6d5  6. f1g2  6... f8c5 This variation has become popular since Caruana used it in his 2018 match against Carlsen. Of course there is nothing wrong with the main line, 6...Nb6. 7. e1g1  7... e8g8  8. d1c2 A new try. This move was played by Carlsen in a rapid game this year. 8... c6d4 The game quickly goes down little-trodden paths. 9. c2e4 The first new move. 9... d5c3  10. d2c3  10... d4f3  11. e2f3 The precise way to capture. Otherwise Black can try a plan with f5-e4, gaining space. Now White can press on the e-file and play f3-f4 at some point. 11... f8e8  12. f1e1  12... c7c6  13. f3f4  13... d8b6 Now it's not so easy to protect the f2-pawn. 14. c1e3 The exchange of the b2-pawn for the e5-pawn leaves the position unbalanced and sharp. 14... c5e3  15. e4e3  15... b6b2  16. f4e5  16... c8f5 An important move, developing the bishop and controlling the b1-square, preventing one of the rooks from threatening the black queen.