Spellcasting attribute

[Enarion]

Hi,

Just wondering about where to specify which attribute a custom class uses for spellcasting. Some use INT others use WIS or CHA, and since the value of these affect how powerful a spell you can cast or if you get bonus spells and so on... I find it important to know how to change this attribute.

I have looked in the spellcasting class tutorial, but I can't find an answer there, it just use the sorcerer template for the battlemage so I suppose the battlemage also uses CHA as its casting attribute.

But say I would like to create the new spellcasting class Treehugger who use DEX, just for the sake of argument... how do I do that?
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