I've been starting Kage's + Health Pot
Blue Crystal, Red Crystal, Catalyst, Blasting Wand, RoA. (In that order.)
Boots 2 (Merc/Ninja)
Frozen Heart or Force of Nature (Depending on enemy team)
Then build the one you didn't. [Occasionally I grab Glacial Shroud and then build FoN, finishing FH after.]
Sometimes I'll grab Philo if I feel I'm going oom too much.
Poison first priority (Besides Ult.), early level in Fling, Mega Adhesive second priority. Leveling Fling increases damage and mana cost. Leveling Mega Adhesive gives a more potent slow.