Lee sin

Once you get Lv.2 technically you can start to pressure if not kill. Just keep farming but always be aware of enemy jungler's positioning and opportunities in lanes.

Well, this is really the case with all junglers. Farm but keep your mind on pressure and opportunities. Just don't force a gank or a fight if the time isn't right.

Once you get your ult you get a huge power spike in terms of ganking.