These guys are inexpensive, they don't use wood like the archers, they have a ranged attack, and they are pretty powerful in large numbers. When you hit the Iron Age, you can build Scythe Chariots and Armored Elephants and you'll see more upgrades than were there before. Scythes are a close-range attacking chariot upgrade. An army of these baddies with some backup can kick some serious butt. They are priest's worst nightmare.
Scythes also do surrounding damage to units due to the spikes on the end of their chariot wheels.
Very Ben Hur. Armored Elephants serve as great steam-rollers. Like the Scythe, they do area damage to units surrounding it. Rise of Rome introduces the Camel Rider . This interesting close-combat attack unit was designed to counter the Cavalry unit and cavalry rush.