The sling is a type of weapon. It is used by loading a piece of ammunition (e.g. a rock) into a pocket with a rope attached. The pocket is then spun and the ammunition is released, which can seriously hurt or kill a person. Madelyn introduces this weapon to the Ranger Corps as the first female Ranger. It is a powerful weapon, yet does not exceed the power of a bow.
Slings have been used for thousands of years for hunting and warfare purposes, as well as a recreational activity. The most well-known story about the use of a sling the story of David and Goliath.