What happens once Atilla comes to power?

So, I am playing as the Western Roman Empire, with a good bit of Mods. 1 of which is a mod that turns each year into 12 turns. I currently have almost wiped out the Eastern Roman Empire, defeated, allied, or puppeted everyone else. I think Atilla has been born, but he hasn't come to power yet. My question is what happens once Atilla comes to power? Is there just dozens of Hun armies everywhere with really good/experienced units? Do they become super aggressive? Cuz right now I have like 4 Hun armies that aren't doing anything other than raiding, and haven't fought me in like 6 turns that I am shadowing with 2 legions. Is it worth it to just sit there and keep ending my turn until he comes to power? Or once I conquer everything else, is the game not worth continuing?