Sniper

The Sniper is one of the three weapon upgrades available at level 10, and is the most used upgrade. It's long range and powerful bullets make it very nice to use. Sniper does 66% percent damage of one bar health/shield per shot, although this is the highest damage possible. Exact values are unknown.

Countering
It is very hard to defeat a sniper unless either you have a sniper and a nearby teammate has a sniper. Because of the Sniper's fast fire rate, long range bullets and high damage bullets, it's difficult, but not impossible, to dodge them. The best way is to either get a sniper and practice dodging, or get an assault rifle. Pistols can work if you're up close enough that the bullet cant hit the person, but its risky. Shotguns wont work either because you need to get close, and usually the closer the more damage it does, or at least ensures a hit for the sniper. If you have good aim, it can be nearly impossible to be killed in a 1v1.

Using
When you have a sniper, the main people to target is anyone that is low on health (a little bit less than half HP, which will give you an insta-kill) or if you're in a team, anyone that's near you. It's not good to just kill everyone in general because there might be a huge army from another team that can easily kill you. Either kill everyone when your in a team, or kill people with low HP. Its ok to chase people because of your long range, as long as you can aim well.