Preservation can fuel Allomancy, (Minus Atium.) but can Ruin fuel Hemalurgy? (Or Atium?) And could Sazed fuel all three Metallic Arts?
Both gods could, if they wanted, fuel all of the metallic arts. Preservation is stronger at fueling Allomancy, Ruin stronger at fueling Allomancy or Feruchemy when it has been given via a spike. Both are balanced when it comes to Feruchemy. But this rarely comes up in the books, as it required expending power in a way that the gods were hesitant to do.
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