I'm trying to design a sniper scenario, and I've got some ideas for the basics. Ideas or criticisms welcome. This is what I envision:
The PC's are walking through an area and are shot at by a sniper, they take cover, and so the encounter begins.
If the players have binoculars, they recieve a boost (or less difficulty) in using their Perception (other suggestion?) skill to spot the sniper. If they succeed, they spot the sniper. If they fail, they do not spot the sniper. If they roll threat, they get shot. If they roll advantage, the shot misses.
They can use their Coordination (other suggestion?) skill to move deftly to the next piece of cover. Maybe 10 meters at a time. If they succeed, they make the distance. If they fail, they get shot and only make it part of the way (threat vs advantage in this case?).
They keep proceeding like this, spotting and moving (perhaps the sniper moves after each shot, needing to be spot again). Until the players get in range, make another spot check, then can fire on the sniper.
This makes the battle more about using skills and coordination than a straight shoot out, but the players can still be injured.