Example game from the 2020 Women's World Championship

In the 2020 Women's World Chess Championship match, Aleksandra Goryachkina played Mark's Opening in game 12 and won against the World Champion.

Link to game where's there's a diagram of the chessboard:
https://www.chessgames.com/perl/chessgame?gid=1990728

Here's the moves of the game without a diagram:

2020 Women's World Chess Championship, Game 12
Aleksandra Goryachkina (White) v Ju Wenjun (Black)
Opening: Mark's Opening

1. d4 d5 

2. Nc3 Nf6 

3. Bf4 e6 

4. Nb5 Na6 

5. e3 Bb4+ 

6. c3 Be7
7. a4 O-O 

8. Bd3 c6 

9. Na3 c5 

10. Nf3 Ne4 

11. h3 f5 

12. Nb5 c4
13. Bxe4 fxe4 

14. Ne5 Nb8 

15. O-O a6 

16. Na3 Nd7 

17. Nc2 Qe8
18. f3 Nxe5 

19. Bxe5 Bd7 

20. Ne1 Qh5 

21. Kh2 exf3 

22. Nxf3 Be8
23. Qe1 Qg6 

24. Bf4 Qe4 

25. a5 h6 

26. Nd2 Qh7 

27. e4 dxe4
28. Be5 Rc8 

29. Rxf8+ Bxf8 

30. Qe2 e3 

31. Nxc4 Bb5 

32. b3 Qe4
33. Rf1 Qc6 

34. Qxe3 Qe8 

35. Qe2 Qg6 

36. Rf3 Kh7 

37. Qf2 Bc6
38. Rg3 Qf5 

39. Qe2 Rd8 

40. Ne3 Qf7 

41. Qd3+ g6 

42. Rg4 Bg7
43. Bxg7 Kxg7 

44. Nc4 Bb5 

45. Qg3 Bxc4 

46. bxc4 Rd7 

47. Re4 Qf6 

48. Qe3 Rd6 

49. c5 Rc6 

50. Kg1 Qf5 

51. Rf4 Qg5 

52. h4 Qe7
53. Qe5+ Kg8 

54. Rf6 Kh7 

55. h5 gxh5 

56. Qf4 e5 

57. Qxh6+ Kg8
58. Qg6+ Kh8 

59. Qxh5+ Kg8 

60. Qg5+

3-3 with 6 drawn. The match ends in a draw, and went to tie-breakers, which were eventually won by Ju Wenjun to retain her title.

A brand new chess opening

Mark's opening

1 d4 Nf6
2 Nc3 d5
3 Bf4

As the early development of the queen's knight prevents the move c4, you would be well advised to play e4 if possible, and aim to develop your pieces quickly. The 2nd and 3rd white moves can be played the other way round, as can black's 1st and 2nd move; after 1 d4 d5 2 Bf4, 2 ... c5 is more likely, which makes 3 Nc3 rather an unwise move though.
Also, when playing this opening, watch out for attacks on the pawn at b2.
The main line continues

3 ... Bf5
4 Nf3 e6
5 e3 Bd6
6 Bd3

6 Ne5 is a sound alternative move here too. Assuming 6 Bd3, the main line continues

6 ... Bxf4
7 exf4 Bg4
8 h3 Bxf3
9 Qxf3 0-0
10 0-0 Qd6
11 Ne2 c5
12 c3 Nbd7
13 Rfe1

Variations (white can usually play exactly the same first 6 moves):
Alternative 5th moves for black:

Variation 5

5 ... Bb4
6 Bd3 Bxc3+
7 bxc3

White can later play c4 to get rid of the doubled pawns.

Variation 5.1

5 ... c5
6 Bd3 Bxd3
7 Qxd3

or...
Variation 5.15

6 ... cxd4
7 Nb5

Alternative 4th moves for black:

Variation 4

4 ... c5
5 e3 Nc6
6 Bb5 (or Bd3)

or...
Variation 4.05

5 ... cxd4
6 Nb5


Alternative 3rd moves for black:


Variation 3


3 ... Nc6


4 e3 and then 5 Nf3 works OK here...


4 e3 Bf5
5 Nf3 e6
6 Bd3


But I think Nf3 and e3 the usual way round works slightly better

Variation 3.1


3 ... Nc6
4 Nf3 Bg4
5 e3 e6
6 Be2 Bd6
7 Ne5 Bxe2
8 Qxe2 Bxe5
9 Bxe5 Nxe5
10 dxe5 Nd7

White can then play f4 and castle.



Variation 3.2


3 ... Bg4
4 Nf3 Nc6

which transposes into the above variation, variation 3.1.

Variation 3.3

3 ... g6
4 Nf3 Bg7


transposes into the Grunfeld reversed/symmetrical variation.


Variation 3.4


3 ... c5


Here, I think playing e3 and Nf3 the other way round is best


4 e3 e6
5 Nf3 Be7
6 Bb5 or Bd3