A crossbow resembles a cross between a bow and a rifle, making it popular with Wookiees, vampire slayers, and hunters today. As with. How Crossbow Works, it fires projectiles with a fast-moving string, and it also has a stock and trigger, like a rifle. On the basis of these similarities, some believe the inventor of the crossbow modified a rifle and attached it to a bow. In comparison to guns, crossbows have been around a lot longer. Archaeologists have discovered crossbows.