Cross-system Investure

[Ink]

I am relatively new to Brandon Sanderson,(around 9 months since i read my first book, Steelheart) but have read almost every book (WOT are the only books i haven't read) How would different forms of investure affect each other? ex: mistborn with AonDor, Elantrian with stormlight, Radiant with Hemalurgy etc.

[RShara]

Welcome!  Have a cookie

 

Wow, what a doozy of a first question.  The answer is.......really complicated, because each one would affect the others differently, and we don't have a lot of information on that interaction.

We know that hemalurgy can be used to steal power from any magic system.

We know that stormlight can be used to fuel Returned so that they don't need to live off of peoples' Breaths.

We know that stormlight is an easy investiture to convert to use in other systems.

We know that allomancy (Mistborn) would be really hard to get working with another system.

Brandon has described using one magic system to power another as "hacks." 

Each person wanting to use another magic system than they normally could would need to hack the system to get it to work.  We've seen Vasher hack it so that he can use stormlight instead of Breath.  He hasn't, however, figured out how to use stormlight for Awakening.

 

Here is a good collection of Words of Brandon or WoBs about hacking investiture.  https://wob.coppermind.net/adv_search/?query=hack

 

Beyond those, we're not really sure how hacking investiture can or does work, just that it can usually be done.  Sorry for the less-than-complete answer!

[digitalbusker]

The answer is going to vary a lot from combination to combination. We have been told by Brandon that any kind of Investiture can power any magic system, but it's not always simple to accomplish.

The easiest one, probably, and the one we're pretty sure we've on screen, is a Nalthian Returned using Stormlight to satisfy their one breath per week requirement.

[Dunkum]

The short answer is it varies a lot, partly because the different kinds of investiture behave differently.  we know a few things:

Hemalurgy should work about the same everywhere, for instance.  And the Returned from Warbreaker can live on Stormlight even more easily than they do breath.  For the rest, we know certain effects should be pretty universal (bronze allomancy should allow the user to detect other types of investiture, for instance, if they knew what to look for), but its hard to say what could or couldn't go together in what ways.

[StanLemon]

Arguably Fabrials and the technological uses of Ferruchemy/Allomancy would be able to synergize pretty well together