User blog comment:JBox2D/Reylin Walker/@comment-6719710-20140702080425/@comment-24090662-20140703031214

It's supposed to be basically instant but with a clear windup time beforehand. Think of it as being impossible to dodge once it's fired, like a Xerath Q.

Haven't really thought about the balance of the item much. I should probably bring it down to 20% AD and 60 AD though, given the penetration attached to it.