sniper

A sniper is a military or paramilitary marksman who engages targets from positions of concealment or at distances exceeding the target's detection capabilities. Snipers generally have specialized training and are equipped with telescopic sights. Modern snipers use high-precision rifles and high-magnification optics. They often also serve as scouts/observers feeding tactical information back to their units or command headquarters.
In addition to long-range and high-grade marksmanship, military snipers are trained in a variety of special operation techniques: detection, stalking, target range estimation methods, camouflage, tracking, bushcraft, field craft, infiltration, special reconnaissance and observation, surveillance and target acquisition. Snipers need to have complete control of their bodies and senses in order to be effective. They also need to have the skill set to use data from their scope and monitors to adjust their aim to hit targets that are extremely far away. In training, snipers are given charts that they're drilled on to ensure they can make last-minute calculations when they are in the field.

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