Today my friends and i challenged Diablo in Nightmare mode when an unexpected bug occur. At the time when Diablo lost some hp and started to warp us all to his shadow dimension, i was being stunned and trapped within his jail. So when we got warped to the shadow dimension, the stun effect on my character didn't wear off. Even when we are backed to the real dimension, the effect is still there. So i had to have Diablo himself to put his judgement on me for the rescue, so that i could be revived later on and gather some loot.
It was okay for me to have encountered such a bug, since i played in multiplayer mode and at a not-very-hard level. But it would be such a pity for someone who do the solo, or playing in extreme difficulty to be stunned forever like that.
In the end, i just hope this post is clear enough for you to understand xD