Ninja Poison MM really shocked me as did Ninja Ninja Stalker
the ninja seemed so squishy but it wasn't until I got the MM binds and learned to micro them into ffocused attacks that I found that they hit like trucks, when combined with poisons seriously nasty debuff ability I was able to steamroll my way through incarnate content.
my ninja ninja stalker because my first ever 50 for a villain side on live. the intitial attacks seemed almost lackluster but the ability to restealth almost immediately meant I could basically one shot almost anything including bosses anything I didn't one shot was so badly damaged that a quick attack rotation would finish them off. Or if it didn't I could vanish and assassinate almost immediately to repeat the process as often as needed