God of War has either come from leveling up cryptarch and once from a blue engram. I know I've received about 4-5 of them, so you'll get it eventually.
English
-
My cryptarch is lvl 29 :(
-
Also, drops off of crucible. I don't PvP much, but I did grind from level 1-5 during Iron Banner and got a few shaders as rewards during that.