X-Com: Enemy Within Sniper Build Guide
While the abilities for your soldiers in Enemy Within are very similar to their Unknown counterparts, it's good to take another look at how all the abilities can work together on your soldier now that Enemy Within has added more goodies. The first soldier I will look at is the Sniper.
This is the classic head shot ability. A straightforward, 30% bonus to critical chance on a shot and an increasing amount of bonus damage to crits based on the rank of the soldier. It has a two turn cooldown.
I usually save this shot for attempting to take out big enemies such as the Muton Elite or a Cyberdisc. Once you're running the high-powered sniper rifles, like the Plasma Sniper Rifle, the damage will be getting close to the 15 or more mark on a crit.
Snap shot lets you use your sniper like any other soldier, allowing them to move then shoot or go into Overwatch. The only downside is that those shots are given a -10 aim penalty. This could be offset by the sniper keeping a S.C.O.P.E item with them. This allows you to reposition the sniper at the last minute and still take a Headshot with them if needed, or put them in a very powerful Overwatch position after seeing where all the enemies have moved.
Squadsight lets your sniper sit in one spot and not have to move near as much. The idea behind this ability is that any enemy you can see with any squad member will also be visible by the sniper. That's not an entirely accurate description of the ability, as it will still be limited by walls and obstructions. However, it seems the farther the sniper is from the target, the better chance the shot has to hit. Squadsight shots cannot crit unless you are using Headshot with it. This ability is far stronger on open area maps that allow the sniper to see targets at incredibly far distances. Combine this with the ArchAngel armor and you should not have to worry about many obstacles to your line of sight.
Gunslinger gives you a +2 damage to pistols. This is one of the simplest and most plain abilities I've seen in the game. This would be a good ability for the sniper that took Squadsight if you aren't planning on making flying snipers. This allows the sniper to still have significant damage potential on a turn they moved by using their pistol instead. Considering that the Sniper Rifle can become hard to hit with at close range, the sniper can switch to a pistol that can do lethal damage as well at close range. This also comes as a benefit to Covert Operations. Operatives can only carry pistols. The +2 damage allows them to be dangerous on Covert Missions as well.
Damn Good Ground
Damn Good Ground gives you +10 Aim and +10 Defense when you have the height advantage over your enemy. This ability combos with the ArchAngel armor and Squadsight to give you a sniper that can shoot nearly anything on the map.
Disabling shot lets you disable an enemy's weapon with a shot that hits at a slight penalty. This ability can pay off in many situations. You can disable a weapon before running in front of a dangerous enemy that's on Overwatch. You can also disable a weapon on a muton or other dangerous enemy if your squad simply can't escape their line of sight before the end of your turn.
Your other option at Lieutenant is the battle scanner. It allows you to use your snipers action to throw a scanner that gives line of sight to your squad. This scanner will not cause enemies to scatter normally, giving you an opportunity to launch a rocket into a perfect cluster of enemies. The scanner will also allow a sniper with Squadsight to see those enemies as if a squad member was there. If you can catch a group of enemies with the scanner, they will all likely be without cover, making them excellent targets.
This ability grants a +10 Aim against targets with less than 50% health. I'm a big fan of using my snipers on big targets, not the easy to kill. I don't see much use in this ability when you can have Opportunist.
Opportunist helps support a Snap Shot sniper. Since you get to move around more and still set up Overwatch, it goes a long way by removing the Aim penalty on reaction shots and also gives them the ability to cause criticals. Nothing beats an Overwatch shot critical that takes out a huge enemy that could have flanked your squad.
Low profile turns partial cover into full cover. This is a huge benefit that allows your sniper to jump behind a small rock and still get the benefits of a wall.
In The Zone
Your sniper doesn't lose an action to kill a flanked or uncovered target. This could allow your sniper to empty all their ammo killing enemies. This ability also works on reaction shots. Most enemies aren't in cover while they pulling a reaction shot, so it should allow reaction shots as long as you have ammo.
Double tap allows the sniper to use either action for a Standard Shot as long as the sniper doesn't move. This can be good for a Squadsight sniper if he has more than one target available on his turn. It can also benefit a build with Snap shot. He can move and shoot or shoot twice if he does not need to move. This benefit must be used immediately. If there aren't any targets that the sniper can shoot right away, he loses the chance. He can't use it later if your squad manages to push an enemy into his sight.
My sniper from above has the build with Squadsight, Damn Good Ground, Disabling Shot, Opportunist, and In the Zone. I usually prefer Double Tap and Snap Shot together, but I'm trying out In the Zone. I've heard good things about it.
Let me know any combos I might have missed or any builds you really enjoy playing.