Rotom-C (Skeleton)

#2
Bouffalant / Sawsbuck should probably be mentioned in C&C as long as they have sap sipper, especially Sawsbuck since it also resists electric, but then there's HP Fire so Sawsbuck is a check at best.

edit: on the choice sets atleast
 

Endorfins

Your Worst Nightmare
is a Contributor Alumnus
#3
I think that magneton should be mentioned as a counter especially if rotom isnt running hp fire, although trick does take away its eviolite