This guide is for going mid and killing everything on the map. Spamming cold feet at level 1 is crucial to winning your lane and is especially devastating to melee heroes. Cold feet as they go for a last hit and they either stay for more last hits and get stunned, or they run and miss last hits. After you get your core items (Bottle, Treads, Wand, Aghanim's) you can really get anything you want.