Wights can't be killed with dragon glass. They are frozen meat and the dragon glass breaks against their flesh and bone. Fire is the most effective. because they are undead it's somewhat unclear what happens when you hack them to pieces. They seem to continue to fight short of limbs. I can't recall whether we've seen a headless body continue to attack. Conventional weapons work. You do not need Valaryan steel.
5/31/15 at 8:05pm