[Gameplay Bug] Zac Untargetable every so many auto attacks.

Played a normals with Vayne with enemy jungler as Zac. Everytime he came in to gank, his normal sling shot animation wouldnt play, instead he would be running in the air.

Whenever I would try targetting him while he's just walking around (not currently using skills or anything), my auto attack clicks would randomly cause me to walk towards him, even walking on top of him in one extreme case.

The amount of basic attacks that actually hit him, were just as random as the walking clicks. I tried right clicks only, attack move clicks, checking to make sure none of my keys were stuck, but nothing.

I was playing Blue side at the time, and when he was being targetted, he was mainly out in the open, no fog of war obscuring him.
(if this will help with replicating the bug.)