I'm going to have to agree with dubesor that vanish is a terribly bad choice at this stage, although abra24 has acknowledged that it might need to be improved. Getting the bonus 20% exp from "Cunning" is definitely worth it though. I don't see a reason to put my talent points into the duelist tree DPS skills when I end up killing monsters with ambush and 1 or 2 hits anyway...
@valen: What class are you and where are you grinding? My is grinding at Hinterlands right now, level 45 with Scarlet Monastery Dungeon achievement. Just earned 0.14% for a Level 41 creep and 0.20% for a Level 48 creep
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