Sisters of Battle
In the fictional universe of Warhammer 40,000, the Sisters of Battle, also known as the Adepta Sororitas, are an all-female army of warrior-nuns attached to the state church of the Imperium of Man. They focus on hunting and destroying heretics, often working alongside members of the Inquisition. The heraldic symbol of the Adepta Sororitas is the Fleur-de-lis.
In the tabletop miniatures wargame, the Sisters of Battle are a playable army.
The latest ruleset for the Sisters of Battle is available in the Codex: Adepta Sororitas, which was published as an e-book.
They have unique game mechanics based around faith and martyrdom. These mechanics allow a most units to aquire a buff for one turn of the game. Since this buff is based on faith and not psychic power; counter-measures designed to defeat psykers have no effect on Faith powers.
The Sisters possess no psykers among their ranks, but they are allowed to use psyker auxiliaries (most often from the Inquisition).
The Sisters of Battle are not superhuman like Space Marines, but they do wear power armor and wield similar weaponry. Their power level is therefor between the Imperial Guards and the Space Marines.
They have a fondness for flame weapons, as they see great symbolism in "cleansing fire", which orientates them towards short-range combat. In the later releases a so-called Holy Trinity of bolter, flamer, and melta became a staple of their weaponry.
Overview in fiction
The Sisters of Battle were officially founded in 36th Millennium by the Ecclesiarch Alexis XXII as Ordes Militant. They were formed in the aftermath of a coup d'état by the previous head of the church. After the usurper was deposed, the Imperium decreed that the church could no longer maintain any "men at arms". The wording of this decree left a loophole permitting an all-female force. Most Sisters are orphans who were abandoned to the care of the church.
The Sisters are led by an Abbess and are organized into Orders. There are Six main Orders and a host of smaller orders. As the militant arm of the church, they are tasked with suppressing witchcraft and heresy, and guarding the Imperium's shrine worlds. They often work with the Inquisition, as their responsibilities overlap.
The Sisters bear a resemblance to several knightly orders from Medieval Europe, such as the Templers and have a strong Gothic feel. Many of their heroines have the personae and attitude of Joan of Arc (especially in Martyrdom and Sainthood). Being an elite army of female zealots, they also bear some resemblance to the Fish Speakers from Frank Herbert's Dune universe
The design of the models themselves have a strong fire motif. They also take the Gothic appearance of the Imperium to the extreme: the Exorcist tank is shaped like a pipe-organ on treads. Forge World produces alternate versions of their tanks, which have a more "military" and less gothic look.