I think its acts as a new "faction" vendor, so getting it to a certain rank allows you to buy their weapons and armour, every level gives you a package that has a chance to weapon of queens wrath that isnt for sale, the blue skinned fallen themed legendary weapons come from the 34-35 PoE and the brown skinned fallen themed exotic weapons drop rarely in the 35 PoE

fun fact: PoE also drops Queens weapons.