Investiture Rules

[Inky]

What are the rules for making a magic system in the Cosmere, considering they all follow the same basic laws? Which ones do we know? 

[+Slowswift]

Also, from a writerly perspective, there's Sanderson's Three Laws to consider.

[RShara she/her]

Sorry, I'm not sure what you mean? Are you wanting to come up with your own magic system? Or you just want to know about the ones that exist? There are a lot of rules and we don't know most of them yet, sadly.

[Calderis he/him]

All we know is that a magic system develops due to the interactions between a Shard, and the planet they've invested in. All worlds have a magical focus that is utilized in every system there... But we have only a few of this confirmed. 

Metal for Scadrial, Forms for Sel, and Commands for Nalthis. 

A Shard doesn't actively shape their magic system, but they can nudge/alter things. 

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Kaimipono

On a broader level, is hemalurgy officially dead, then? Or is it still extant in some Ruin-free (but still messy) form? (If it's gone, is there any imbalance since Preservation's magic power is kept and Ruin's isn't?)

Brandon Sanderson

Is Hemalurgy dead? No, not at all. It, like the other two powers, was not created by Ruin or Preservation, but by the natural state of the world and its interaction with the gods who created it. It still requires the same method of creation, but very few people are aware of how it works.

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