csmath: Advance CK has been popular weapon of Svidler [eliminated in WC precisely with Andreikin's CK], Shirov, and Caruana among others. 3. ...c5
[Igor Khenkin's sideline. Khenkin himself lost three CK games in this year's Dortmund, two in his own line and one of them against ... Andreikin. Obviously this is what Andreikin has been studying.]
The line
5. ...e6
is a new [as in novelty!] attempt and it does not look very convincing even though it is one of the top choices of Houdini.
13. ...Bc5?!
14. ...Qb6?!
17. ...Bb4?!
[misterious attempts to control short diagonal a5-e1 or attack on f2, it is hard to figure out what was the intention of Andreikin. These moves on queenside look quite planless.]
Nepo keeps on delaying kingside attack but eventually he starts
25. g3! h6?
[facilitating white attack but black is in a difficult position because kingside attack will obviously take place while his bishops are shut out of the action. This move provides white with a new target, weakens kingside castling notable g6 square, and cuts off one possible escape route of knight on f5. It is an absolutely disastrous positional error in already difficult position.]
26. h4
[obvious and expected]
26. ...Qe8
[what to do, black is practically playing crammed onto the last rank with one bishop completely out of the action and the other pointing aimlessly.]
26. ...Nxg3?!
[desperate attempt to muddy waters since the knight is stuck while white attacks kingside.
28. ...f6, 29. g4 fxe5, 30. Nxe5 Nd6 31. Nxc5 bxc5 32. g5 c4, 33. Bg6 Nxg6, 34. hxg6 seems more passive with likely decisive attack of white.
However this still looks like accessible defence and while it might not be enough it is not immediate capitulation. Andreikin move in the game is hopeless.]
29. Nxc5! Nxh5
30. Nh2 bxc5
[Getting h-knight is going to leave black without any countergame. White is now a piece up and the game is effectively over. White even has a supported passer on b5.]
Resounding defeat of Andreikin's Caro-Kann. His setup from the opening was a complete positional failure. The planless attempts with dark-squared bishop simply led to a waste of time while white was [hesitantly] organizing decisive kingside attack.