Can you explain how Allomancy etc are powered by gods’ bodies?
The powers of Ruin and Preservation are Shards of Adonalsium, pieces of the power of creation itself. Allomancy, Hemalurgy, Feruchemy are manifestations of this power in mortal form, the ability to touch the powers of creation and use them. These metallic powers are how people’s physical forms interpret the use of the Shard, though it’s not the only possible way they could be interpreted or used. It’s what the genetics and Realmatic interactions of Scadrial allow for, and has to do with the Spiritual, the Cognitive, and the Physical Realms.
Condensed ‘essence’ of these godly powers can act as super-fuel for Allomancy, Feruchemy, or really any of the powers. The form of that super fuel is important. In liquid form it’s most potent, in gas form it’s able to fuel Allomancy as if working as a metal. In physical form it is rigid and does one specific thing. In the case of atium, it allows sight into the future. In the case of concentrated Preservation, it gives one a permanent connection to the mists and the powers of creation (i.e., it makes them an Allomancer).
So when a person is burning metals, they aren’t using Preservation’s body as a fuel so to speak–though they are tapping into the powers of creation just slightly. When Vin burns the mists, however, she’d doing just that–using the essence of Preservation, the Shard of Adonalsium itself–to fuel Allomancy. Doing this, however, rips ‘troughs’ through her body. It’s like forcing far too much pressure through a very small, fragile hose. That much power eventually vaporizes the corporeal host, which is acting as the block and forcing the power into a single type of conduit (Allomancy) and frees it to be more expansive.
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 strongest at fueling Allomancy. Ruin is best 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.
What was the other lake in Alendi’s book?
A manifestation of Ruin’s gathered consciousness, much like the dark mists in book two. The lake was still around in Vin’s era, but had been moved under ground. (Note that the Well is a very similar manifestation. You’ve also seen one other manifestation like this….)
Does this new world have atium?
If atium was the body of Ruin then it would seem when Sazed took up Ruins power he would have reabsorbed all of the atium. New atium then would be bits of Sazed’s new powers and weaken him with each newly formed bead. It would seem then that if atium exists it would be much rarer, and mean that Sazed would not be able to control this process.
It’s theoretically possible for Atium to appear in the future, but right now Sazed has no plans to release any of it to the people. It is, effectively, now something of myth and legend.
Would the Three Metallic Arts operate in other worlds, or are they direct results of Ruin and Preservation and thus only operate in Scadriel?
To use Feruchemy or Allomancy in almost every case, one must have the right spiritual and genetic codes, imprinted upon people during the creation of Scadrial by Ati and Leras. To use Hemalurgy, one must first have someone with these right spiritual and genetic codes, then take the power from them. Other people on other worlds are not going to simply discover the Three Metallic Arts by accident.
Is Sazed/Harmony effected by the metal blindness, or can he see things written in metal?
He is blinded by metal.