Spotter
A shooting partner with a high-magnification optic whose job is to observe target impacts, read wind off mirage, and call corrections back to the shooter.
A skilled spotter is the shooter’s second set of eyes, and at long range, often more important than the shooter’s own optic for confirming hits. The spotter calls the impact (“low and right, half mil come up”), reads mirage between shots, and watches for environmental changes.
Most precision rifle competition allows a spotter; ELR matches almost require one. The team’s wind-call accuracy is what most often keeps those long shots on target.