I don’t know what you most violent story is currently, but that shadow thing that appeared on your screen is normal. The shadow connects to the story, and you’ll understand why once you get to the active lava zone (around 1450 meters, and to find it you need to find a hole that leads deeper, I think it can be found at the entrance maybe?) But just so that your prepared, the shadow will appear on your screen again once you enter the lava zone, or was it the active one? Well, it doesn’t really matter which lava zone, but just know the shadow will be back.

-Lamprey