I am just suggesting for the humans, for magic ( seeing as they got none at the moment), i suggest this:
A Non-combat or Combat wizard, or some sort of unit that can turn livestock ( Sheep, pigs, Cows and Chickens) on fire.
Then the livestock can ether be shot from a trebuchet or can simply run towards the enemy burning everything in its path and then explode or something along those lines when it reaches/ heading towards its target.
Would be quite funny seeing flaming animals heading towards you, would it not?
Also i got this idea when thinking about the orcs wargs, and thinking since, they can fight and be a food source of food, I thought why not make the human source of food dangerous, as a "last stand" kind of thing.
Well i hope this gets in, would like a change from all the serious battle scenarios to a more funny, yet dangerous and interesting battle scenarios, with this idea.