@Riot- Gragas W Bug
I just played Gragas and every time I was in a really close range to perform the W-enchanted basic attack the animation of Gragas slamming the unit didn't happen and instead he just performed an idle or walking animation. It seemed to happen only when I was really close to the unit I was about to slam with my barrel auto attack.
EDIT: Forgot to mention that while it doesn't perform the animation correctly,** the barrel slam AA still does damage**, just without the usual animation.