The End
After that close call, Xiao Xi made the rest of the way quite easily. After experiencing the first half of the bridge, the latter half was a lot more manageable, especially given that they were used to the feeling by now.
How did we know she got across safely?
Well, she used Sound Magic to amplify her own voice and call out to us from across the bridge. This way, even though we couldn't see her figure past the gap in the middle due to the fog, we could still know if they made it across. It also seemed like she could use magic again on the other side, which was interesting.
That being said, if we got a person with Sky Magic over there, I doubt they could just fly back and carry the rest of us across. I was pretty sure this 'trial', if it was one, didn't work like that, unfortunately. This 'Grey Scourge' wasn't that stupid, if it could cause this much destruction and surprise with its attacks.