So yeah, Thousand Cuts? Completely broken. I don't mean flask of fire, obviously that's broken and a bug. I mean just using it at focus 3, regardless. I one shot Sandy Howler(the lvl 20 dragon in Hissing Wastes), I'm too lazy to go unlock the dragons in Emprise just to check but since he was dead when I was only about 2/3 done with Thousand Cuts and I don't even have the best gear or superb dragon slaying enchant, I have no doubt I'd one shot these too.
Part of it is how easy it is to stack damage% modifiers, how easy it is to get 100%crit and +100%crit damage as a rogue, as well as 70%armor pen. But most of it is really just how stupid the damage the ability does. 38hits at 400%weapon damage(with a ring) is like, derp balance levels.