Investiture Conversion Rates

[+Invocation]

How much Stormlight = 1 Breath? We know Vasher is able to get enough to stay alive, but how much is that? Does he have to stay out in the highstorm for the duration, or can he just suck the Stormlight from spheres? On that note, if he somehow got to Taldain, would he just be able to sunbathe to get his Investiture supply? How much would that need? What are the conversion rates for various forms of Investiture?

[Pagerunner he/him]

Excellent questions, which unfortunately Brandon and his team hadn't even quantified yet, last we heard (back in December):

Quote

Questioner [PENDING REVIEW]

Do you have-- Or have you determined an equivalency between how much Breath it takes to make a certain gem's worth of Stormlight?

Brandon Sanderson [PENDING REVIEW]

I have recently assigned Peter to this task, and he is feeling overwhelmed by it. It was actually during the writing of Oathbringer where I finally said, "Yeah we need to standardize this, so start working on it." So it was like, "Oh great". Which means he has to read through all the books for references and start figuring it all out. And we're going to need like an equivalent of a jewel or something like this, right? *gestures to a sphere that a fan made* And we've been putting it off because it sounds like an awful lot of work. 

So the answer is no, we don't have it yet. It's something I've known for years we're going to need. And on this book, I just started saying, "All right.  I'm going to have them do all the stuff they need to do. And then you're going to tell me how many spheres they need to start with." Right? Like, I write the book, and then we retrofit how many spheres they needed to have how much Stormlight, so that we could be consistent with that.

But we haven't done across magic systems calculations, yet.

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