Also, would the Elantrians and the Lerasium-mistings be considered Slivers? Or is just the Lord Ruler and Vin Slivers (Via the Well)? Or do you need more power to be considered a Sliver?
Elantrians are not slivers. Mistborn trilogy spoiler warnings follow! The Lord Ruler was indeed a Sliver. So was Vin. For the rest, I would say probably not.
What defines an actual Sliver of Adonalsium is not as clear-cut as you might think. It’s a term that in-universe people who study this have applied to various existences and states. Every single person on the world of Scadrial has a bit of Leras in them—a bit of the power of Preservation. Every single person has a bit of Ati in them. There’s a certain threshold where these scholars would call you a Sliver of Adonalsium. But I would say that any regular Misting is probably not a Sliver. A full Lerasium Mistborn is getting closer, but people who have held one of the powers are what would probably be termed a Sliver by the definitions. If you hold all the power that makes you a Shard, but the Lord Ruler held a little bit of it and then let it go. From then on they referred to that change in him—the residue, what was left—as a Sliver. When he held it he became the Shard for a short time, and Vin was a Shard for a short time. After Vin gave up the power, what Kelsier is at the end of the trilogy—that’s a Sliver of Adonalsium.
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