Also created is a defensive field that can protect the Witches from the Neuroi's miasma as well as other physical weaponry, making them humanity's trump card in the war. With the Striker Unit equipped, they gain the ability to fly and their tapped magical potential provides the strength to utilize weapons far too heavy and powerful for a normal person. In order to bring out their potential for use in battle, each Witch equips a unique machine onto their legs: the Striker Unit. As the miasma seems to be unable to spread across large bodies of water, humanity has designated such areas as their main lines of defense.
Not only do normal humans have no defense against this miasma, but the remnants of the land affected by it are processed by the Neuroi into new weapons, crumbling huge sections of former nations into the sea.
The weapons of the Neuroi mostly take on forms similar to aircraft, but their most troubling tactic is the spreading of a corrosive miasma. This puzzling enemy force has appeared frequently and without warning in many areas across the world throughout history. The titular Strike Witches are young women with high magical potential who are recruited into militaries around the world to fight against the enigmatic Neuroi, which began an invasion of unprecedented scale on human territory in the year 1939. Set in a world similar to Earth in the mid twentieth century, Strike Witches tells the story of a fight to protect that world using a combination of magic and technology.
See also: List of Strike Witches characters