Unique unit (Age of Empires II)

An Unique Unit is ostensibly an unit type in Age of Empires II that is only available to one civilization.

Overview
Each civilization in the game has one unique unit that can only be trained at the Castle in the Castle Age, but eight civilizations have access to a second unique unit that is trained at another building.

Before Age of Empires II HD: The African Kingdoms was released, a Castle was required to train the second unique unit. Since that was changed, the civilizations with two unique units gain the advantage of instant access to a unique unit once the Castle Age is reached.

There are roughly three categories of unique units: Castle units, non-Castle units and shared units. As the name suggests, a Castle unit can only be trained at a Castle, while non-Castle units are created elsewhere (Longboat, Turtle Ship, Missionary, Slinger, Imperial Camel, and Caravel).

Shared units, however, fill a different and broader niche since their nature means that they can be used by other civilizations in addition to their own by simply allying with their native factions. A team containing an Italian or Berber player will have access to the Condottieri and Genitours, respectively. Shared unique units are Team Bonuses.

Apart from the Imperial Camel and the Condottiero, all unique units are available in the Castle Age.

All but four (Slinger, Condottiero, Imperial Camel, Missionary) unique units have an Elite version that possesses overall superior statistics. The upgrade is always available in the Imperial Age.

It is worth noting that the Samurai possesses an attack bonus against all unique units (including itself) but the Imperial Camel, which is technically just a unique upgrade. It is the only unit that has an attack bonus against unique units.

List of Unique Units
All in all, there are 35 unique units:
 * 11 Infantry
 * 10 Archers (including 4 Cavalry Archers)
 * 7 Cavalry
 * 3 Gunpowder Units
 * 3 Ships
 * 1 Special Unit

The Age of Kings
Note: The Goths can train Huskarls at the Barracks after researching Anarchy.

The Conquerors
Note: The Huns can train Tarkans at the Stable after researching Marauders.