Which  practically sacrifices a pawn.
1. d2d4  1... g8f6  2. g1f3  2... g7g6  3. g2g3  3... f8g7  4. f1g2  4... e8g8  5. e1g1  5... d7d6  6. f1e1 Not a very  common way to transpose into the Fianchetto Pirc, although the likes of  Kramnik, Aronian and Ivanchuk exploit it quite often. 6... b8d7  7. e2e4  7... e7e5  8. b1c3  8... b7b6  9. h2h3  9... c8b7  10. d4d5  10... d8e7  11. c1g5 A novelty and a typical provocation.  White is fighting the freeing c7-c6 advance as early as possible. He  intends Qd1-d2, therefore Black's next move is more or less forced. 11... h7h6 Firouzja is not afraid of the possible tempo gainer on the  c1-h6 diagonal. 12. g5e3  12... a8c8 But this looks inaccurate. 13. d1d2  13... g8h7  14. f3h2 Now White obtains strong control of the d-file. 14... c7c6  15. d5c6  15... c8c6 Awkward, but what else?! 16. h2g4 From the Pirc Black got into a Najdorf type of position and since his pieces are sowewhat awkwardly placed for the play in the center his  position is worse. Therefore Firouzja goes for: