What does "nulled my client" mean? The client stopped responding (allows input, but does not process input, animations still played) The client stopped responding at all (no animations, no inputs) The client crashed to desktop or invoked a windows crash error dialog If it happens again, can you get me you log? That would help immensely to track down what the issue is.
It's probably from something else rather than the ability itself. I play 2x Call of the Hunter champions without any problems, since the new client was out. The ability never crashed client for me