Gruenfeld with Bf4 e3
1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. Nf3 Bg7 5. Bf4 O-O 6. e3
White moves the queen's pawn to d4. Black develops the knight to f6. White plays the c-pawn to c4.
Black plays the g-pawn to g6. White develops the knight to c3. Black plays the queen's pawn to d5.
White moves the knight to f3. Black develops the dark-squared bishop to g7. White develops the dark-squared bishop to f4.
Black castles kingside. White pushes the king's pawn to e3.