6dc5455c____The_Coppermind___17th_Shard__Entry
[Chapter] 70 [Entry] 
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.
The Hero of Ages/Epigraphs - The Coppermind - 17th Shard
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