healing from a shardblade?

[Cyanic he/him]

(spoiler for WoR)

We know a windrunner like Kaladin can use stormlight to heal a "severed" arm caused by a shardblade (and presumably other Radiants can too, haven't read OB yet)

So two candidates: Can a gold compounder heal from a shardblade cut, and can someone given a Returned's Breath heal from that same cut?

[Calderis he/him]

You don't even need to be compounder. 

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Questioner [PENDING REVIEW]

If a Shardblade was put through Wayne's eye, would he able to use his ability to *inaudible*

Brandon Sanderson [PENDING REVIEW]

Yes, he should be able to heal that.

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And as to a Divine breath, it was able to heal Susebron's tongue even though he'd been without it for decades. I think it would function as a single burst of essentially "perfect" healing. While this one is more opinion than fact, I'm confident it would work. 

[Dunkum he/him]

I doubt we have anything definitive on that, but given that a gold compounder can heal from dynamite and a returned breath heals so well that it restored the power of speech to someone who would never have been able to develop it in the first place, I'd say the answer is yes.

[Weltall]

To add a bit to what @Calderis said on compunding, remember that almost anything a compounder can do can also be done by an ordinary feruchemist, assuming sufficient time is given to store a given trait. They just can't do it nearly as easily. See Wayne, who can perform amazing healing as long as he has enough stored health and Miles-level healing with the unkeyed goldmind. The obvious exception is that Rashek's trick to prolong his life required compounding to get around the zero-sum nature of ordinary age storage.

And I agree that Divine Breath healing should work too. It healed Susebron even though he'd never known a time when he wasn't tongueless, so between that and his upbringing his Cognitive self-image probably included that and would have filtered any normal healing, but in this case it didn't and his tongue was healed. True, he needed that tongue to Awaken rather desperately but I'm not sure immediate need can override an ingrained image of self that easily.

[+Extesian he/him]

This particular WoB also strongly indicates that healing with Divine Breath will heal anything that other magic systems can heal, but even more strongly. 

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Questioner

Given Sanderson's Laws about limitations...

Brandon Sanderson

Yes.

Questioner

What would you say are any spiritual, cognitive, and or physical limitations to a Returned's healing ability?

Brandon Sanderson

That they can do it once.

Questioner

That they can do it once, and that's it?

Brandon Sanderson

Yeah, right? The Returned get one heal and then they die. That's a pretty big limitation. Like you have to choose really well. However, what they can heal is bounded by cosmere limitations on healing, but it is a supercharged version.

Questioner

Okay. Could you define more cosmere limitations on healing?

Brandon Sanderson

Cosmere limitations on healing can be affected by your own perception.

Questioner

Okay. Cognitive stuff.

Brandon Sanderson

Cognitive stuff. And so there's a part of that, and... But that's really-- cognitive interferes. And if your spirit is gone? Right? Cosmere healing, you know, if your spirit is passed on you just get a dead body even though you've healed it.

Questioner

So potentially Vasher, having a much greater cosmere knowledge than others could potentially have a much greater usage of that healing than regular--

Brandon Sanderson

Well the healing-- What I mean by that is yourself. You impose limits. So the person being healed can impose some limits on the healing working. It doesn't happen as often as I'm making it sound. But, you know-- why Kaladin's scars have not healed, right? So Kaladin being hit by a Returned would still not heal his scars. He's got a major hangup about those scars.

Footnote: The questioner seems to have been asking about cosmere healing in general for Returned, but Brandon focused on their ability to give up their Divine Breath to heal somebody else.
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