Wrong answer.
And the holo walls were solid walls.It´s the vehicles themselves who time travels.
Well,can you guess what will become of the castle on Trabia-Balamb era?
If you can it will help you see what the black thing is.
Also look at the weird shape of the castle´s floor near the edge.What did it resembles?
Note that the black thing seems to move like wind(it has nothing to do with the helixes theory).
