In addition to the main lines of the Huebner (i.e. the closed positions arising after black plays for the d6 and e5 pawn pushes) - black can strike against white's center with 8... d5. GM Dzindzichashvili breaks it down for us in "layman's terms" today, and provides truly interesting insight on black's middlegame approach (including when and when not to capture on d4).
