[Gameplay] Diana Moonfall buggy interaction with Sion ultimate

As the video description says, Sion's forward leaping ground slam (Second cast of Sion's ultimate) has a buggy interaction with Diana's moonfall and possibly other CCs. Moonfall cancels the forward movement and animation, bugs the timer/channel bar and drags Sion towards herself.

It does not however, cancel the area of effect damage which will be pulled along with Sion. But it was incredibly confusing to say the least.