A big surprise. I've never seen this move before. Can you imagine this is only the 15th most-popular move in the position $2 It was played by a GM just twice before, both times in blitz games. So it's safe to say that this is nearly a new idea.
1. g1f3  1... d7d5  2. g2g3  2... g7g6  3. d2d4  3... f8g7  4. c2c4  4... c7c6  5. f1g2  5... g8f6  6. e1g1  6... e8g8 The system with c6-d5 in the Grunfeld Fianchetto has been played in thousands of games, even at the world championship level. It's one of Black's most solid options.