So I just started recently to play Rome Total War, but besides just playing the tutorial, I've played the game only using EB. It's an awesome mod by the way, and my thanks to everyone who was responsible for its creation. However, I have a question, and I hope it isn't too stupid. In original RTW, the Romans have archers, ballistas, and onagers, but in EB, I can't seem to find out how to recruit these units. Are they not in EB for some reason, do I need to get one of the reforms to access them, or have I not constructed a certain building? Those units seem like they'd be a real help in battle, yet I can't seem to get them.

Sorry if this is a really dumb question or a subject that's been discussed a million times before I got here.