It would be definitely interesting to hear the story of scythian victory in this scenario, because I just played this scenario as scythian and I have no clue how to win this game.
They say that Scythians were not conquered even by Alexander and it seems rightly so. Despite 5 double flag rolls (which killed 3 of my units) I managed to concentrate enough range firepower to outmaneuver heavies and get to light/medium ones. Picture lacks 5th banner for Scythians (for 5-4 for Scythians):