Imagine walking around the desert at night, and then you get the message “the sands shift around you ominously”, and then scarabs pop out of the sand. It would be amazing.
I also like the idea of falling into small rooms, or temporary mini dungeons. For example you could fall into a hole, and it turns out to be the lair of a dry lich and its phylactery/canopic jars.
+1 to the idea in general.