#1 - Oct. 29, 2013, 8:33 p.m.
There could be a book Cain left hidden somewhere random (or even laying around in a hidden spot in his house) that instructs players on how to create the Legendaries from the raw materials that drop.. that could give quests to obtain and use specific locations, crafting equipment, monsters (a demon blacksmith or crafter that you have to beat in combat to get him to help you?), and dropped loot to complete a certain Legendary. A Polearm and/or Spear crafted from Belial's Horn. A Hellcat fur pelt Chest, Pants, and/or Shoulders crafted from a dropped Hellcat Pelts. Got quite a few more ideas if there is positive reception to such things.
GAR