Black has other strategies to counter 1.e4 and 2.d4. A pair of related possibilities are 1...d6 and 1...g6. When either of these moves is played early in the game, the other move soon follows, reaching positions like shown in the diagram.
Black plans a long-term undermining of the White center by moves like ...c5 and ...e5. This opening is a distant cousin of the King's Indian Defense.
