Unicorns are a race of pony that have the unique ability to directly wield, channel, and manipulate magic. This ability is powered by a single horn of variable length, texture, and color on their forehead, which also serves as the sole distinguishing anatomical feature of unicorns compared to other pony races.
Before the War
The use of magic allows unicorns to perform delicate tasks easily, such as sewing. Most spells and abilities are open to all unicorns, but each unicorn usually has a specialty, be it teleportation, telekinesis, or medicine. Generally unicorns have a collection of various spells relating to their specialty, one being vastly more effective than the rest.
During the War
The unicorn approach to fighting is slightly different than that of the earth pony or pegasus. While they are able to wield a battle saddle or a weapon in the same way, it was often more comfortable to control weapons with telekinesis. Projectile weapons aside, unicorns were also able to channel raw magical energy as either offensive attacks or defensive wards.
With the weaponization of gemstones, unicorns were able to modify weapons to either enchant ammunition being used, or to fire pure magical energy.
After the War
Much like before the war, unicorns generally find themselves in very specialized roles requiring delicacy, such as medicine. Unicorns find themselves at a disadvantage when it comes to ideal candidates for slavers, as they carry a high value even if unable to at as laborers.