Wizards and Arcana Rifles
In the world of Atlea, Wizards who are trained for war are called Battle Mages and wield devices known as Arcana Rifles.
These rifles use special shot-and-powder prepared daily by battle mages, corresponding to individual spells. A skilled Battle Mage can quickly load and fire this shot in a matter of seconds, and the practical effects of the spell are as described in the 5E Player’s Handbook.
Battle Mages train in specialized colleges dedicated to the art of war, and craft their own, individual rifle over the course of their training. It is said that each rifle is as unique to it’s owner as a thumbprint is to a man.