B17 23
+1 Battering Ram 8 - ...has nobody ever used these things? They are, bar none, the most drastically effective unique unit in the game. They lose the general purpose properties of a Spearman, but gain, you know, the ability to single-handedly take multiple capitals. There is literally no other Civilization that can boast the ability to completely eliminate another Civ by turn 10. The Huns can do that easily if you happen upon the very common instance of a Ruin upgrading your warrior. That early on, they will take away half a city's health in one attack, and even well into the Classical era, they will still shear away enormous chunks off a city's defenses while only taking marginal amounts of damage. When supported by Horse Archers (which are basically Ancient-era Camel Archers), the factor of getting trashed by melee units is nonexistent, and it is hardly a difficult matter to get the Rams in there to just completely pulverize a city. This is a strategy you can start working out after researching only about 5 early techs, and remains effective until basically the early Renaissance, by which point you'll have easily conquered most of the world. I've succeeded handily with this strategy on Immortal on a Standard Pangaea map, and had completely conquered all but two civilizations. The only reason that even occured was due to a Fractal-like map and hitting a roadblock on Portugal's super defensive terrain (and even then that same military of Rams and Horse Archers, cut in half by Portugal's Frigates, still managed to annihilate both them and Byzantium). Nearly every other UU in the game is, at best, solid but incapable of going it alone and requiring significant backup. Four Rams is enough to destroy any city in one turn up until they get Armories. The only unit that can even maybe do something similar is the Siege Tower, which outright comes an era later.
Berber Cavalry 16
Camel Archer 33
Carolean 35
Chu-Ko-Nu 34
Conquistador 12
Cossack 27
Horse Archer 16
Hussar 13
Hwacha 15
Immortal 10
Impi 32
Jaguar 24
Janissary 31
Keshik 35
Longbowman 33
Minutemen 21
Naresuan's Elephant 24
Pathfinder 34
Sea Beggar 27
Ship of the Line 36 these are unmatched on water maps
Siege Tower 34
-3 Tercio 15 - Mounted units are just too rarely used for this to be worthwhile, especially since Pikemen are still running around and capable of holding themselves over into the Renaissance (and can upgrade into Lancers anyway). I definitely think this unit should be genericized into a Pike & Shot unit that's the standard Renaissance Pikeman upgrade (so that the Lancer can be a Knight instead), and Spain given a UB or UI (I rather like a Seaport replacement with drastically lower Production cost and double the bonuses when built overseas, meant for getting colonies in the New World up and running fast) in their place. I am very much in support of each civ only getting one UU and a Building or Improvement in the second slot.
Winged Hussar 24