What is your favorite unit?

[Avicenna]

Well, light lancers used properly can destroy the cataphracts. If the cataphracts continue shooting when charged by LLs, LLs can just retreat and charge again. If they choose to engage in melee, the faster LLs can lead them into spears. When they stop chasing, if they do, charge again.

Warman: I'm assuming all you're talking about are the Sassanids. If you are, their spearmen are rubbish, though admittedly better than the Limanentai (can't spell). The elephants, cataphracts and clibinarii are vital but not your core units, since they're so expensive and take so long to recruit.

[Conqueror]

Except for Clibinarii Immortals, which you get for free as they're the general's bodyguard. They even regen their losses automatically. That unit is basically closest thing to perfection you can get:
- Super high morale so they rarely ever break.
- Extremely well armored.
- Armor piercing melee weapons.
- Long range missile weapons & Persian Shot ability.
- Extra HP.
- Against infantry, outrun & outmanouvre them and then smash them with a charge. Will beat anything but the elitest (ie First Cohort) foot units easily this way. Against the elites just keep skirmishing for a while and soften them up with arrows, then charge to finish them off.
- Against cavalry (heavy & light), simply melee them.
- Against faster horse archers, missile duel. The Immortals' superior armor will protect them. If the HA use Cantabrian Circle then approach them at marching speed to tire them.

The only real weakness is that you only get as many of these units as you can get family members.

[Empirate]

Granted, Legionary Cohort (who have come up several times now) as well as their forerunners, the Hastati and Principes, can do most everything you want them to. But how boring is an army consistin of allround meleers? Favorite units for me have to be something fancy, or at least something interesting to play tactics-wise. I haven't tried Light Lancers yet, but as I'm currently playing Carthage, I must say there's not many jobs (except sieges...) that Round Shield Cavalry cannot do. A quarter to half of my armies consists of Roundshields, even though Long Shields are easily available. Why? They're recruitable everywhere with just stables, they're cheap, fast, expendable. And you can rout armored hoplites and whatnot with Roundshields, if you have a good sense of timing. First-tier units are the way to go: Easily retrainable, easily produced in masses. And using all-cav armies you're fast on the campaign map.
I know that Round Shields aren't exactly what you'd call fancy, but they're definitely the most important unit in my Carthage campaign. Going for something a little fancier, how's War Elephants? Basic Eles stink: They die easily, their impact seems to be a lot weaker, they have no missile attack, and they can't be upgraded. But War Elephants, while expensive, will never die on you if used rightly. I have an army with four units of War Eles in it that have seen more than a dozen field battles plus some six or seven sieges. Only a single Elephant has ever died! And don't think they don't see any action: I usually charge them in headfirst, followed up by cavalry. That's often enough to completely rout the enemy. So the huge initial investment pays off big-time, and you don't ever have to retrain them. The additional time and effort you have to invest in armored War Elephants doesn't pay off greatly: The additional armor doesn't make that much of a difference.
Somebody mentioned Cretian Archers: These guys rock, but they're recruitable in small numbers only, unfortunately. Nevertheless, in one Bruti campaign I had an army with six of them in it, accompanied by the usual Roman legion-stuff. I didn't need cavalry support: The Cretians could often pick apart the enemy so completely I wouldn't have had time to flank anyway. The moment my melee troops were readying their pila, the enemy fled, reduced to less than half their numbers regardless of armor or shields. I managed to beat Phalanx-heavy armies easily without flanking them, just by wearing them down with missile fire until their morale broke.
I also like Onagers a lot, for instant city assaults as well as for attacking field battles: I just love the sight of a firepot hitting square into the middle of a dense formation. And while I only ever fought two bridge defenses with Onagers, those were just sweet.

[Lorenzo_H]

Out of ballistas, repeteaing ballistas and scorpions which are the best? I have seen many different opinions and the three are all so unique from each other. I know they arent very good and I try to avoid them but seeing as a couple of my automanaged settlements bought some I decided to try them out.

[GeneralHankerchief]

Out of ballistas, repeteaing ballistas and scorpions which are the best? I have seen many different opinions and the three are all so unique from each other. I know they arent very good and I try to avoid them but seeing as a couple of my automanaged settlements bought some I decided to try them out.

Although I have no experience with Scorpions, I'd have to go with Repeating Ballistas just for the sheer firepower. An experienced crew can absolutely annihilate units, even faster than my precious Cretans...

[Lorenzo_H]

Although I have no experience with Scorpions, I'd have to go with Repeating Ballistas just for the sheer firepower. An experienced crew can absolutely annihilate units, even faster than my precious Cretans...

but shot for shot Ballistas are more powerful than Repeating Ballistas.

[Quillan]

My personal favorite is the legionary cohort, for all the reasons mentioned. Rome was historically infantry heavy anyway, and I usually play like that. My usual "field army" consists of 10 legionary cohorts, 4 archer auxilia, 2 roman cavalry and a general. I'll add more as needed depending on the foe I'm facing.

As to the engines, I've recently started using scorpions in certain battles, mainly because in my current campaign Armenia has become quite powerful (they took over the Parthian starting lands, the city of Seleucia, and two of the Pontic provinces.) So, now I'm up against a mix of crap infantry, decent infantry (heavy spearmen and armenian legionaires), crap missile troops, and gods on horses. My usual army wipes the field with all the infantry, but those cataphracts cause horrendous casualties whenever they get into combat. I hired a couple of units of merc hoplites, and had one of them run over by a unit of cataphracts (not generals bodyguards, just the normal cats). Scorpions have a longer range than either the ballista or repeating ballista, and does enough damage that if you manage to hit the unit, you'll kill 1-4 people with every bolt. It doesn't matter how armored they are, they die. Once the unit gets down to only 1-2 ranks deep it becomes much harder to hit, but until then you hit them regularly. I haven't had the chance to use repeating ballistae yet; I just finished building a couple of them but they haven't made it to the battle area yet.