While not as heavy as Cataphract the Roman Cavalry are a force of momentum able to crush their enemies. I've found that they are quite good at pushing through their enemies during combat to improve a flank attack as a support unit. They can quickly wrap fights up and move on to their next soft target.
@Fiskey is playing Julius Caesar with 3 skirmishers and i'm playing Scipio Africanus with 3 Roman Cavalry and the match goes quite well. The enemy fields many heavy infantry but isn't coordinating it properly to their advantage and our a large organised force gets many small battles to fight over the course of the match that we overwhelm with ease.
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