Question for those in-the-know:

On an outside map, I have characters on the ground with barrier. My opponent's team is on the roof of a building. I erect a barrier in the middle of the playing field. Can my opponent's team fire over the top of that barrier and hit me, or is it high enough to block their fire entirely?

Thanks in advance.

There LoFs will all be blocked by your Barrier. When firing from elevated terrain against grounded terrain---your LoF can cross the blocking terrain in your own square, but any other blocking terrain acts normally.