Well, to state the obvious: These things are huge, powerful, and your army barely qualifies as an appetizer for them. Oh, and they have an shitload of health, too. And while they're certainly are a menace, I'm pretty sure that they have a few weaknesses. Like how they might be vulnerable to certain Combat Arts; come to think of it, I thought I saw one of the students learning one during the part in the Treehouse vid where they were training the students. But as for what happens after attacking them four times, I'm guessing that it either weakenss them or it just pisses them off. I'm really hoping it's the former, because who wants to be killed by a overgrown rat?