What is the hardest opening to play chess?

What is the hardest opening to play chess? Its simply decided by its usual sharpness. Hard openings: Sicilian, Kings pawn game, Alekhine, 2. Nf6-scandinavian, pirc/modern defence, Scotch game, Birds opening, Benoni defence, Chigorin defence, Kings indian attack and kings indian defence and all gambits (that I know of).

Its simply decided by its usual sharpness. Hard openings: Sicilian, Kings pawn game, Alekhine, 2. Nf6-scandinavian, pirc/modern defence, Scotch game, Birds opening, Benoni defence, Chigorin defence, Kings indian attack and kings indian defence and all gambits (that I know of).