Yata

I think the amount of Investiture someone may take from Shards is too low also combined to made you Ascend. (for example the amount of Susebron's Breath are a meaningless amount of investiture compared to a Shard's one). Also if for hypotesis Hoid (or someone) take so much Investiture from every Shard. I doubt He/She may ascend with it. But He/She with the right knowledge may merge those investiture to restore some Pre-Shattering Investiture...The implications of something like that are unknown, maybe someone who read some unpublished material may know more

If we talk about my hypotesis...Yes it will work (but I am unsure if pure Atium will work or you need a specific alloy)

As far as I remember Roshar's Seasons are quite random (or determinated by unknown factor). Spring may actually became winter or summer or fall. EDIT: @Djarskublar was faster than me XD

Actually you don't have to that Shard's Investiture. You need ONLY a great Connection to the Shard. Vin may Ascend to become Preservation because her being was deeply Connected with Preservation...but not because she was a Mistborn, his mind and all was about to protect. Sazed in the same way became connected enough to Ruin only in the HoA during his darkest moments as faithless. As an example from Secret History: Notice also that Hoid is made by the same template of the original Vessels (yolen's beings) ...If they are capable of pick up the Shards. Hoid will capable also (if it's only a matter of kind of Investiture.

It's more a direct choice of Endowment, who Intercept the deadmen before they reachs the Beyond and offer the chance to return. Probably a Divine Breath is made specifically for a Returned and then when the Returned dies The Divine Breath return to Endowment. Of course there must to be some requirement to be choosen by Endowment, but I don't think you have to pass for the same issues of a Radiant Spren's Bond

Yes it's what I meant, sorry for be unclear. Of course it's an hypotesis born by the idea that Ruin doesn't spread his Investiture in the same way of Preservation. With this idea the rest is pretty obvious but of course the idea at its core may be wrong

Yeah pretty simple, I know

Sorry I was far far from my town: It's quite simple to be honest, but I made you wait for a while and a good idea didn't come EDIT: OF course after posted this, the good idea comes

Yes man, I didn't mean you was wrong. But only that he wasn't sure he may outlive her

I think it's possible there are some Cognitive Shadow of Adonalsium somewhere (or maybe his Cognitive Shadow is the Beyond itself) but I find unlikely that he survived the golpe. We have a WoB that said "The Shattering happened becaused they killed him"

This last part may be really untrue. I explain myself better: An Elantrian have an infinite lifespan and in this you have right. But Brandon said that be an Elantrian is a stressful life and after a while it's too much for an Elantrian. When this happen he simply left himself die (as Galladon's Father). Unless Sarene died young, they will have at least 30-40 years together.... Maybe Raoden may reach his limit before of her. PS: About this stressful way, I imagine it's caused by the constanct stream of Dor in their body and some form of Savantism who made the stream powerfull with the time.

I had a theory about some hidden limitation of Hemalurgy, but until now I didn't have the chance to ask to Brandon. I think that Ruin (or Harmony) doesn't not provide Ruin's Investiture to made an Hemalurgic Spike and an Hemalurgist have to provide this Ruin's Investiture from the victim or from the spike. This (if I have right) mean that you may spike every Scadrial native with whatever metal you want (actually also people who have integrate artificially some Ruin's Investiture). But you need an Atium Spike (pure or alloy) to Spike foreign human.

I considerated this possibility some time ago. But someone posted me a WoB who said that the Divine Breath are not sapient and this stop me to develop further the theory. To be honest I think that the "a breath every week to stay alive" may be a proof of the mortal's soul in a Returned. I interpret this as the Investiture needed from the Returned's soul/mind to avoid the call of the Beyond. It's a deadman after all.

I think the Original Feruchemist gained Feruchemy through Lerasium and Preservation's istructions but anyway if Kel is a Fullborn now. what is the point in crafting the BoM ? The Southerns though without the BoM he will be powerless (or at least not so powerful) if I don't remember wrong.

Once there are a WoB (I will post here when I found) who said you may stole a Shardblade with Hemalurgy and it's quite the same thing. But remember that if you "stole a Spren" you may have some strange effects as for example kill him with an Oathbreaking. The Spren's bond is very dependant from the Human's partner habit.

I am just became a Soulcaster, farewell my old Forger self. I left my elegant Soulforgery art to convert myself to the brute force Soulcasting.... Shame on my and my lost art

I imagine four is the limit for Human based Constructs, as we see the only counter example is about a Mistwrath based Construct.... Probably there are other factors: for example if Allomantic Copper is helpful aganist this kind of control, an Inquisitor/Smoker would be harder to affect (but we have no proof about)

I can't say for the other part of the question (about Blessings and decay) but I have the strong feel that a Hemalurgic Spike at full power or just with a little charge left is the same for the purpose of Hemalurgic control. I think it's meaningless how big is the gifted chunk, the Spike to inject those Spirit-web cause the same backdoor. I think (but it's not a perfect proof) that the end of SoS's show quite well this point.

I rememeber that one of them said that his field of study was the math, but maybe I am wrong.

Actually Wayne would be capable of compound Nutrition (what a Bendalloymind keep) and Wax would be able to compound Speed. Of course if someone provide to them some Unkeyed Metalmind of the right metal. Yes you have right, without complete Feruchemist the only way to obtain a Medallion from nothing is with Hemalurgy. But once you have an Feruchemical nicrosil and falluminium medallion. You are able to start and industry (if it's possible to store F-Alluminium ability) with this Alpha-Medallion alone. This is true and false at the same time. Once you have what I called Alpha-Medallion, you may give it to someone with another Cosmere's magic and made him store it in NicrosilMind (at least the ability keep in the SpiritWeb).

The Interlude about the two Ardents and their measurements of Spren. NEW QUESTIONS: Did Nightblood improved its power from its Creation ?

Yeah, but I find unlikely that Vasher didn't fix Nightblood if the sword is so easly to repair. Maybe an interesting question would be, "Did Nightblood improved its power from his creation ?" (I will post now in the List of Question)

Yeah I know, it's only my interpretation of the Spren capture... It may be horribly wrong

I think it's possible to gift to Nightblood other Breath (with the standard command), but I actually don't know if this extra Breath would be parked as regular Breath or become part of Nightblood as a being. To be more precise, I don't know if extra Breath are capable of made Nightblood grows as Splinter

I have not reference for this. But from the informations, seems that a specific cut is able to capture a specific spren and only the Artifabrian (and later the Listener) developed the method (but the Listeners may have some spy as Artifabrian's Slave and they simply stole gem or informations)