Draven Ult Bug

While it is possible for skillshots to get displaced while being grabbed/ pushed back (Ie Draven ult, Lux ult, etc) I don't think that this is what should be happening.

What I thought was most strange was when I went to dodge the ult (I thought he would cast it to the bush from his original position so I went to walk way from the wall) it basically followed my movements. It could be a coincidence though. It seems as if the ult began to cast after Draven was pulled, but the ult wanted to go at the angle it was originally pressed so it changed direction.