Black is winning.

Supported by a tactical variation, White improves his rook and now threatens 2 Rd6.

Or 2...f5 3.Re1 and the passed pawn decides – Smagin.

The point. Black has no defence against the attack along the b1-h7 diagonal.

Black resigned.

Withdrawing the queen from the exposed d4-square before taking actions on the kingside.

1...e5?! 2.f5! White takes over on the kingside.

White is slightly better.

Exploiting the fact that after 1...Qxc5 2.Rc1 followed by Nc7, White creates a protected square on d6.