Lore: There once a a very powerful craftsman who made armor and weapons that could protect him from almost anything and kill anything in his path, He terrorized Holds and upset the divines so they squished him with a meteorite and left his gear for crafting at the whiterun forge The End 

As the "Lore" that i totally

didn't make

up says there is OP gear at Adrianne Avenicci's forge (Behind it)