Trying to put a list of things that walls and floors let through.
Snipe( if casted before LOS)
Pretty much any projectile ignores LOS if they leave the caster before the LOS block occurs (i.e. the target is in view, projectlie launches, target moves behind cover, projectile still hits).
Snipe (and dark flare, and crystal frags) don't go through LOS if you get behind cover during the cast time.