Yata

He searched the Skybreaker. Maybe if he becomed One of them (really unlikely) or Simply know some of them...He could be a good broker of Information about the Surgebinder. Or introduce Shallan to the right people.

Not too much, in a challenge Honorblade's user Vs KR. The second Will probably win with the same experience. The reason for Szeth's manace was the years of practice He had with his Power. Anyway I really doubt Amaram's Shardblade is an Honorblade....To be honest It's quite impossible for the evidences we have

Well Rashek had to activelly use the Shard's power to gift himself Allomancy so be a Sliver to default didn't give you Mistborn's power. On another note (but maybe it's better to start a new topic instead of go too off topic there) the Lerasium (for example) rewrite your Spirit Web without change "who you are" so the two things could be done without change the "you" (that is mostly Cognitive). The Investiture want to be used, so it's possible the Spirit-web's "useless part" over time start to twist to accomodate new functions and losing his original purpose. Again, I am not saying this is the way the Cognitive Shadows work, simply we can't be sure any scenario yet. We know too little, as far as we know Honor's choice of giving the Surgebinding via Honorblade to Heralds could be dictated by their impossibility to their Spirit-web to keep this ability in their long time intervals without a physical body. We know too little

His Soul was also replaced by Preservation's Investiture and binded to Scadrial/Realms/Shards in different ways....The difference between a living being and a Shadow isn't only the cutted physical string. So I am unsure He could be again a Mistborn once he returned with a physical body. I didn't mean "He has no more his Allomancy" but "we can't be sure He is still an Allomancer". Of course this doesn't prevent him from gaining Allomancy again with some external source (Hemalurgy/Lerasium/Medallion tech).

He could have picked up Ruin with the same outcome of his Preservation (but without the Ire's orb needed) He was Connected enough to Ruin but he was still a CS, therefore a second class Vessel, with limited access to Shard's possibility and something like that. The same thing will happen for every compatible Shard. Honestly I don't think, Ire's Orb gave him all the Connection to Preservation He needs. If He was a living being probably this would make him Ascend to a Preservation who could actually do stuff (If He doesn't try to act aganist the Mandate), so I think be a Sliver didn't change this thing too much (notice also he was already a Mistborn and spent at least an year in Preservation's perpendicularity...his Connection to Preservation didn't seems significative aganist his natural one to Ruin). Lastly but this is really tangential, I don't think become a Preservation's Slive gave you Mistborn's power or boosts your already present abilities and honestly I am neither to faitful Kelsier retains his former Allomancy after his death.

The Lerasium wasn't there. Rashek had to search and find It. About the North and south perpendkcularities...The clues are really doubtful. we know there is at least a Southern descend worldhopper...Maybe someone of this group was Simply returning to Scadrial.

The plot relevant Ones? You are a weird guy/girl XD

Ok so I avoided spoiler to a certain extent

Before to answer you. I have to ask. What mistborn books DID you read? Anyway Kandra with the appropriate Spike and Method could gain Powers. About the Cooper compound, maybe you could store the same Memory 10 times...I don't honestly know. It's a speculation inside a speculation so I didn't think too much in the details. Notice also Sazed statement is Simply without bases. He can't know the Compound ratio. It could be 2,5,10,16,100 times as far as we know

The melting/merging of Metalmind for now It's a controversial topic. I Will expand when we will know more. You could store in a Spike without problem, the Inquisitors did It all' the time. Hemalurgy is a low Investiture magic system. It doesn't interfere too much with the Feruchemical charge, probably there would be a little loss but something hardly noticable. We don't know the effect of Feruchemical Lerasium. But i don't think could store Allomancy because other metal could already do It. We don't know for sure how the Cooper compound work... Someone think you could Simply replicate a Memory so to allow to store It again without fogert It. Why burning durallumin would male you to store Faster? Your store rate is based by your resource. So from your point of view you are storing ad usual...From the other you could be seen having more charge than they could figure out. But the durallumin is priceful and burns fast. As far as we know for now, Nicrosolminds store Innate Investiture not kinetic One...But It's not a deny, Simply we don't know yet. Ok the tapping alluminium is weird. We don't know if your Identity could be boosted actually. If It could, maybe you will be unable to access your own Metalmind without boosts again Identity. Interesting but probaby nothing. Maybe you could prevent a some degree of Corruption, but hardly to say. Both this thing can't happen. But probably nothing Will happen (Little extra: the Canon term for someone Who hold a Shard is Vessel, Shardholder is the term we used before the canon One was released). I think for now I can't answer more...If I have time later, I Will expand the merging Metalmind part...There is somewhere in the forum a topic about.

That was a problem, not the only one. Kelsier was a poor Vessel for Preservation both for a mundane reason (the one you actually provided) and for a magical reason (his status as Cognitive Shadow). Bè attached to a body didn't make himself whole. He has just probably a artificial string to link It to the physical (like the Returned and probably the Herald). This could help him to worldhop (help not avoid the whole problem, because the problem is mainly in his replaced soul) but I don't think this would provide an help to Vesselhood. He seems uncapable of solving his issue with a Shard's power. I really doubt a Little magic trick could stata in Place when he Will become a mainly spiritual being (Shard). Lastly, I agree Kelsier would probably fit well with Ambition (see below)....Simply I this his situation make him impossible to actually Ascend to It. PS: Kel is a Cognitive Shadow from dome centuries. The Investiture change you over the time. Kel is now quite an Humanspren made of Preservation's Investiture. I hardly could believe, he is the same of Mistborn's books

I have some problem to believe that Slierhood gives him an advantage to pick up. He was already using a trick to become the perfect host and honestly if his time as Preservation didn't improved his chances to manipulate the Shard (I mean while he was holding It)...I really doubt some residues could do something. PS: notice also that Kelsier was already something like a Preservation's Sliver due the influence of Well's Investiture. I don't think there is a good difference between him and Ati After his Death (except one is of Preservation and the other of Ruin)

Aaronator already mostly answered but just to add something. Vasher uses specific command to give away his Breath and a bit of mental gymnastic to avoid to give away his Divine Breath. He is also able to suppress his Divine Breath to appear as a not Returned, how He could do this, is unknown. But probably it's still about mental gym too

This question could be really tricky. Odium was in Sel too and his influence is still there for example. We don't even know if D&D had company in old times there

Wait, you could be right...Simply It's not sure. What I wanted to say is to not take a single and unclear istance as proof for mechanics

Please don't expose your speculations as facts. Trellium Spikes seem to be unseen by Harmony but once he know where you are if your Soul is exposed enough (Number of Spike regaddles of the material). He could Control you. Be unseen and unable to be controlled are separate facts...As you could se with Emotional Allomancy. You didn't feel the target you could influence Before you start to overcome their defense.

There is no evidence about the 16 to be Preservation's Number. We know only It's relevant for Scadrial's magic but is equal linked to Preservation or Ruin...So there is more. This is Probably impossible as Harmony didn't know what the Trellium is...If there is a part of Atium he would be able to recognize at least the Trellium as an Alloy of something Alien and Atium

Some evidence seems to suggest It's the Planet that dictate some numeric rules build in the Magic System (along with the Focus). So probably the Metallic Arts Will express themself as sets of 16 elements regaddles from the godmetal you use to make the set's base itself.

yeah (link)

Nah that is Simply a mechanical consequence of his Powers. Not a specific resonance of being a Crasher. Also Rashek could do it. While the Resonances are something denied to someone with too powers

No problem. I wanted only to point to the weak point of the proposed idea. If something in the Harmonium will give Feruchemical ability I Will propose its allomantical effect...But It's probably impossibile to survive to the experience without some Crazy cirtumstances. So quite impossible to test for the Southern

This is very very unlikely...Or the Southerns Will be all Feruchemists. Something of course impossible or they Will no need of the Medallion's tech we saw them use

Probably I was unclear Sorry. Before I asked the WoB because Theoryland is blocked at work's network. Anyway I am sligthy aganist multiple Resonances. It's possible Truthwatcher's resonance allow/Force them to use the Power differently. (For example without the Memory, they have to slowly "build" the Illusion. Notice also the Surge could work also alone in theory (with Fabrial or through Foreign Magic Systems) or with more than another Surge...(a Radiant with an Honorblade).

I am not sure to follow you. We know the Windrunner and Lightweaving's one and they don't affect the Surges usage. Sure some other Resonance could affect the Surges and give to the user a slight different Surge in pratical usage...But this is not the default case, no all the Surges are influenced by the other One. PS: could you post here the wob about Truthwatcher and Ligtweaver's Illumination Surge ? Because i probably never see that

We know It could be used to interact with other form of Investiture, If he is an external Alluminium effect. The practical usage is doubtful, I honestly don't think you could discharge too much Investiture but without an actual reference It's hardly to say. The only informations we have is about the WoB "Metalmind Vs Leecher" that seems to point aganist the Leecher's efficiency and the BoM's Story showing a Leecher who suppress for a while an Invested Weapon..Again here without know how the weapon works we Can't extrapolate too much