Found a non-harmful, hilarious bug in the keep.
You can attempt to jump off the front gate cliff with Slayer, and end up in a near infinite loop.
The only way I found how to manually escape the loop was to change characters.
I was able to repeat this multiple times.
Video: https://www.youtube.com/watch?v=LtkBta_IAy8&feature=youtu.be&ab_channel=Pabooney