Starting items: Tangoes x2, Sentries, Branches x4
Item progression: Soul Ring, Midas, Treads, Drums, BKB, Abyssal.
Hero is super imba in lane, can 1v2 easily. Use spiderlings to harass heroes, creep neutral camps, and push when appropriate. (Hint: tab selects non-hero units). Use for map vision and anti-gank. At levels 3 and 5 it is possible to try for kills with nukes.
Don't advise Ring of Aquila or Orchid. Manta acceptable in some situations. For mana, soul ring -> treads switch int -> cast. Ult is short cooldown and can be used to push and to quickly heal up.
For the most part this hero already has it all: damage, sustain and applies a miss chance and slow, pushing power, etc.. all you need is a BKB. Biggest issue is late game drop-off--I find straight Abyssal after BKB to be the strongest way to play. Apply pressure to your lane and show them what split pushing means!
High skill hero but very rewarding.