World hopping Radiants and Returned

[Hsien99]

If Radiants or Returned world hopped to different would they still have all their abilities? I would say the Returned would since their breath is basically internal but not Radiants unless you could someone substitute one type of investiture for another. Am not an expert by any means but would it be possible let say a radiant died on Roshar to transport them to Nalthis to possibly become a Returned or let say if Kaladin died could Vasher give him his divine breath. I just have a little theory that now that BS has started introducing other characters and artifacts from the cosmere we might see in book 4 or 5 some possible world hopping maybe.

[RShara she/her]

Since Vasher as Zahel has been on Roshar for some time, there's no problem with Returned worldhopping.  As for Radiants, they would have to figure out how to get their spren off Roshar, since it's hard for them to leave the area where their investiture dominates. 

Spoiler

We also saw Hoid Awaken at the end of OB without any problems, and Vivenna seems to have done quite a bit duing the battles and in Shadesmar, although neither of them are Returned..

 

Brandon has said that each series is meant to be self contained, so worldhoppers aren't going to play a significant role in Stormlight Archive.  They will pop up and have some interactions, but will be cameos and easter eggs.

 

Kaladin doesn't have the right innate investiture to become a Returned.  If Kaladin were seriously injured and didn't have access to stormlight, Vasher could use his Divine breath to heal Kaladin, then die.  That wouldn't make Kaladin a Returned, though. It would just heal him and kill Vasher.

[Calderis he/him]

Becoming returned for a non-Nalthian is exceptionally difficult if not impossible. 

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BlackYeti

In Words of Radiance, we have Vasher showing up... One of his aliases on Nalthis is Kalad, which is very similar to the name of one of the Heralds on Roshar. So I was wondering how far back this connection between him and Roshar goes.

Brandon Sanderson

It goes pretty far back, in fact when I wrote Way of Kings, the 2002 version; he was a main character and was Kaladin's swordmaster. I wrote Warbreaker to jump back and write out his backstory, Vasher's. So to me Warbreaker actually came after Way of Kings. But the connection goes back pretty far, further than you would first guess.

BlackYeti

Did he actually come from Nalthis and not Roshar?

Brandon Sanderson

I'm not going to actually answer that one-- Well I can answer that: yes he does come from Nalthis. It's pretty obvious that the way that the Breath's working, the reason he moved is because it's easier to get Stormlight than Breaths, and Stormlight can fuel being a Returned like him. And so yes, he was born on Nalthis. Becoming Returned without being born on Nalthis would be really hard.

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As for Radiants off world, trying to get the Spren away is the first hurdle, then you have to either find a way to get Stormlight elsewhere (hello Lift), or hack a different investiture to fuel it. 

All magics can be used Cosmere wide with varying levels of difficulty. Sel is the major exception, because the Dor is locked into the planets Cognitive Realm, so it is only accessible there, unlike all others accessing through the the location independent Spiritual Realm. 

[Oversleep]

5 hours ago, RShara said:

Since Vasher as Zahel has been on Roshar for some time, there's no problem with Returned worldhopping.

Actually, that's wrong. Vasher managed to do it, but by no means it's simple and straightforward like a normal person worldhopping:
(emphasis mine)

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Questioner

Have we seen cameos of Heralds on other Shardworlds?

Brandon Sanderson

The Heralds are tied to the system by the magic that permeates them. They could not leave.

Questioner

I thought I saw someone but I guess not.

Brandon Sanderson

It’s part of the magic. Some would call them Cognitive Shadows, right? Whether they are or not. "Cognitive Shadow" is a very ambiguous term in the cosmere. It means, basically your soul-- It's the same thing with petrification, right? Investiture replaced your soul, and permeated your soul, and your soul continues to exist, but... you are usually Invested with something, that's tied, and you're basically like pure Investiture then. You're tied to the thing you're Connected to. Most of the things that you're gonna see with that, travelling is going to be very difficult, unless you know how to do it. You have seen people do it.

Questioner

Who?

Brandon Sanderson

Vasher

Brandon Sanderson

Vasher... You have seen people do it. But anyone who's got-- yeah.

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So I would hesitate to use Vasher as baseline of what's possible.