Predator Rakan
Gyazo
Soo, i've been using this build alot recently. and it's worked surprisingly well.
First off, AP, not tank, rakan.
you start with spellthiefs/refillable, and support like normal. you want atleast 800/1150 Gold before your first back. If 800; Frostfang/boots If 1150; frostfang/Boots/mana saphire. also, you idealy want to be level 6, or very close to it, before you back.
This allows you to predator-ult unto a lane to gank, which is.. surprisinly effective because NOONE expects rakan with predator.