I never did end up getting thorn for year one, but I just finished the year 3 thorn quest. Since I never got the year one version I never had the grimoire. When I received the year 3 version the grimoire never unlocked. Does anyone know if this is a bug or whats going on?
-
try grabbing thorn from the exotic weapons blueprints by the vanguard.
-
I've read that other people have had this same issue and I think it's a bug. The only thing I can suggest is next time Xur is selling Legacy Primary Exotic engrams try buying some until you get a Thorn and maybe you'll get the card that way.