6dc5455c____The_Coppermind___17th_Shard__Entry
[Chapter] 79 [Entry] 
I believe that the mists were searching for someone to become a new host for them. The power needed a consciousness to direct it. In this matter, I am still rather confused. Why would power used to create and destroy need a mind to oversee it? And yet, it seems to have only a vague will of its own, tied in to the mandate of its abilities. Without a consciousness to direct it, nothing could actually be created or destroyed. It's as if the power of Preservation understands that its tendency to reinforce stability is not enough. If nothing changed, nothing would ever come to exist. That makes me wonder who or what the minds of Preservation and Ruin were. Regardless, the mists—the power of Preservation—chose someone to become their host long before all of this happened. That someone, however, was immediately seized by Ruin and used as a pawn. He must have known that by giving her a disguised Hemalurgic spike, he would keep the mists from investing themselves in her as they wished. The three times she drew upon their power, then, were the three times when her earring had been removed from her body. When she had fought the Lord Ruler, his Allomancy had ripped it free. When fighting Marsh in Fadrex, she had used the earring as a weapon. And, at the end, Marsh ripped it out, freeing her and allowing the mists—which were now desperate for a host, since Preservation's last wisp was gone—to finally pour themselves into her.
The Hero of Ages/Epigraphs - The Coppermind - 17th Shard
Entry