Greetings!
Thank you for taking the time to share this feedback. Motion sickness was a concern when we first talked about the possibility of Grimrail becoming a Mythic+ dungeon. Fortunately, one of our designers came up with a clever solution which he was happy to share in the video below:
As mentioned in the video this is currently a one-off solution for places we’ve identified motion sickness as a concern due to background motion, but we hope it’s helpful for those affected and we’ll keep an eye out for any other places where it might be applicable.