[Gameplay] Zac instantly revive after death

So I was in a game earlier today, playing ezreal in flex queue.

When we entered a fight agaisnt their tank, Zac, and thought that we finally killed him, he isntantly revived before the animation of his passive even reaches the ground (as you can see on this video).

I think he used his E at the exact same time that he died, making him revive instantly. It is also important to note that we could hit his passive and kill it and that, on his point of view, his passive DIDNT go on CD.

So this is a pretty gamebreaking bug, hope it can be fixed :D