While the primary use for Windrun is as an escape spell against enemy ganks, it also has uses as an offensive spell. Used aggressively, Windrun allows you to chase down enemies and slow and body-block them for teammates to catch up, and ignore their physical attacks if they try to trade right-clicks with you. The bonus movement speed also allows easier positioning for Shackleshot and Powershot, but mind the mana cost and cooldowns so that you don't get caught short.