Its been a while since I read RoW so I may be wrong on some of this, but this thought came up when reading another post.
RoW - All & Mistborn Secret History
- Do we know what happens when a godmetal is taken into the cognitive realm?
- We know that lower spren have a presence in both the physical and cognitive realm - do bonded spren have a visible presence in the cognitive realm when they are in the physical? In M:SH people show up as lights in the cognitive realm.
- if you can take one of those god metal (or inverted god metal) assassin blades into the cognitive realm, could you kill A) spren B) people using them?
It’s also possible that their functionality requires them existing with a foot in both worlds, so to speak. They’re not dead spren nor typical living spren. They’re willfully imprisoned in some special way. Like, the Oathgate spren are the Oathgates, and seem like they’re more responsive, but we know it’s the same process as the Soulcasters and they’re basically inert. Sanderson has said they’re something like Shardblades, but he doesn’t say they’re just like Shardblades. They do act differently and affect things differently. Presumably they just work differently.