Forrest says someone has already made this suggestion. So if I'm repeating what someone has already said then sorry.
I just thought; in Myth 2. Alric wears special armor which makes him immune to the fetche's lightening. Alric must have got this armor some time after the great war because he sure doesn't have it in the Last Battle but he does have it in Gate of Storms. This armor makes him invulnerable (to a certain kind of attack) in battle, sounds familiar doesn't it?
A bit like the armor described by the head, perhaps Alric went back into the Barrier to look for it and found it.
Normal armor doesn't protect people from lightening (warriors, stygians & brigands all die from it).