The strength of the Lunar Empire is not its soldiers:
In our recent RQ game, my players got a good look at what the real backbone of Lunar power is – it is the Lunar College of Magic – the Crater Makers and horrors like the Crimson Bat. They watch in horror as Lunes, meteors, volleys of Madness and Mindblast, and a Chaos horror routed their much larger army of nomads, Storm Bull cultists, and mercenaries
That explains why Argrath tried to emulate it with the Sartar Magical Union. Yes, exactly, but he needed the defeat at Hender’s Ruins to realise how badly he needed to emulate them.
Arguably, Hender’s Ruins was the last big battle involving the old Lunar Army in Dragon Pass.
To me this is why the Lunars = Romans is so misleading. It leads you to focus on their phalanxes and cavalry units, and not on their army destroying magical units.
When I imagine the Lunar army, it is a cross between Achaemenid Persia and Pan Tang.
So how was the lunar army routed at Dangerford? Dangerford was basically a Sartarite vs. Tarshite fight.