1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1b5  3... g8f6  4. d2d3  4... f8c5  5. b5c6 Caruana is an expert in this variation. The resulting positions are often simple in appearance and complex in essence, with many strategic details. 5... d7c6  6. h2h3 6.Nbd2 and 6.0-0 are more common, but Caruana has played this move already in 2023.