In my Opinion there is no Champ that Counters Skarner away. If you get your Camps, Get Ganks, Kills, Support in early. You will be good. But if you get Focused in early and die 2-4 times this is lost for you... Just farm then. Play him Only in Jungle he isnt a good laner at all.
Maybe some Champs they have Movement and can escape are Counter Skarner but if there is a slow jungler you will get him with this Build.

Pros:
+ CC with Fracture and Ultimate
+ In my Opinion no Champ Counter him hard
+ Ult fcking. OP
+ Gets Very Tanky but also does Damage
+ If u master him good Jungle Clear
+ Can do early kills and good lvl3 Ganks

Cons:
- Hard to Master
- If you dont hit the E under lvl 6 the Gank is failed
- If you die early and fall behind. You cant do anything...
- **** qss