I am sure this has been already reported by someone by now but there is a bug with the skill "Flight of Gaavanir" when you recall the hammer and hold the skill button it causes you to get stuck, unable to do anything unless you die, but if you can't die you will have to force close the game and restart it. This issue happens every single time I try to hold the skill button it seems. Here below is a video I recorded just to show what I am talking about.

https://youtu.be/MeS6xFB95xY