Inferno tactics.

By the way, why didn't you upgrade your Imps to Demons? In the final battle, these poor creatures probably wouldn't have been of much use anyway... but at least you would have had 10 extra Demons. :)

But it still wouldn't have helped. As you calculated yourself, the armies were roughly equal, and the slowdown was the deciding factor. :)

So you don't have to spend a lot of time, I'm posting a small model that I created specifically for such cases :)

You choose the faction, set the number of units, and voila.
You're welcome. :)