Mistborn #03 The Hero of Ages

sheet up, flaring his tin to get a better look at its contents in the darkness.
    " 'Vin,' " he read. " 'My mind is clouded. A part of me wonders what is real anymore. Yet, one thing seems to press on me again and again. I must tell you something. I don't know if it will matter, but I must say it nonetheless.
    " 'The thing we fight is real. I have seen it. It tried to destroy me, and it tried to destroy the people of Urteau. It got control of me through a method I wasn't expecting. Metal. A little sliver of metal piercing my body. With that, it was able to twist my thoughts. It couldn't take complete control of me, like you control the koloss, but it did something similar, I think. Perhaps the piece of metal wasn't big enough. I don't know.
    " 'Either way, it appeared to me, taking the form of Kelsier. It did the same thing to the king here in Urteau. It is clever. It is subtle.
    " 'Be careful, Vin. Don't trust anyone pierced by metal! Even the smallest bit can taint a man.
    " 'Spook.' "
    Marsh, again completely controlled by Ruin, crumpled the metal up until its scratchings were unreadable. Then, he tossed it into the ash and used it as an anchor to Push himself into the air. Toward Luthadel.
    He left the corpses of horse, man, and message to lie dead in the ash, slowly being buried.
    Like forgotten tools.

Quellion actually placed his spike himself, as I understand it. The man was never entirely stable. His fervor for following Kelsier and killing the nobility was enhanced by Ruin, but Quellion had already had the impulses. His passionate paranoia bordered on insanity at times, and Ruin was able to prod him into placing that crucial spike.
    Quellion's spike was bronze, and he made it from one of the first Allomancers he captured. That spike made him a Seeker, which was one of the ways he was able to find and blackmail so many Allomancers during his time as king of Urteau.
    The point, however, is that people with unstable personalities were more susceptible to Ruin's influence, even if they didn't have a spike in them. That, indeed, is likely how Zane got his spike.
    70
    "I STILL DON'T SEE what good this does," Yomen said, walking beside Elend as they passed Fadrex's gate.
    Elend ignored the comment, waving a greeting to a group of soldiers. He stopped beside another group—not his, but Yomen's—and inspected their weapons. He gave them a few words of encouragement, then moved on. Yomen watched quietly, walking at Elend's side as an equal, not a captured king.
    The two had an uneasy truce, but the field of koloss outside was more than enough of a motivation to keep them working together. Elend had the larger army of the two, but not by much—and they were growing increasingly outnumbered as more and more koloss arrived.
    "We should be working on the sanitation problem," Yomen continued once they were out of the men's earshot. "An army exists on two principles: health and food. Provide those two things, and you will be victorious."
    Elend smiled, recognizing the reference. Trentison's Supplying in Scale. A few years earlier, he would have agreed with Yomen, and the two would probably have spent the afternoon discussing the philosophy of leadership in Yomen's palace. However, Elend had learned things in the last few years that he simply hadn't been able to get from his studies.
    Unfortunately, that meant he really couldn't explain them to Yomen—particularly not in the time they had. So, instead, he nodded down the street. "We can move on to the infirmary now, if you wish, Lord Yomen."
    Yomen nodded, and the two turned toward another section of the city. The obligator had a no-nonsense approach to just about everything. Problems should be dealt with quickly and directly. He had a good mind, despite his fondness for making snap judgments.
    As they walked, Elend was careful to keep an eye out for soldiers—on duty or off—in the streets. He nodded to their salutes, met their eyes. Many were working to repair the damages caused by the increasingly powerful earthquakes. Perhaps it was just in Elend's mind, but it seemed that the soldiers walked a little taller after he passed.
    Yomen frowned slightly as he watched Elend do this. The obligator still wore the robes of his station, despite the little bead of atium at his brow that he used to mark his kingship. The tattoos on the man's forehead almost seemed to curl toward the bead, as if they had been designed with it in mind.
    "You don't know much about leading