Attributes:
11 Expertise
10 Wilderness Survival
10 Marksmanship
You should have one whole attribute point left(!).
Skills:
Choking gas, Frenzy, Oath shot (elite), Lightning Reflexes, Distracting shot, Savage shot, Troll unguent and Rez sig.
Start with choking gas + frenzy and use oath shot to re-charge choking gas instantly, if you get attacked use lightning reflexes to evade attacks and to stop frenzy causing you double damage.
There should be a few times where you are stuck without choking gas for about 5-10 seconds so use distracting shot and savage shot to make up for that little period of time.
I'm guessing that with enough R/W's using this skill setup in a team, they could completely shutdown any casters in the targets area.
If anyone does try it could they please post the result?
