Pirc - Byrne variation
1. e4 d6 2. d4 Nf6 3. Nc3 g6 4. Bg5
White plays the king's pawn to e4. Black moves the queen's pawn to d6. White plays the queen's pawn to d4.
Black develops the knight to f6. White develops the knight to c3. Black moves the g-pawn to g6.
White develops the dark-squared bishop to g5.