Aramintai

Nothing is known about her.

Nothing is known about why the ritual maiden was blindfolded. Was she even blind, or just blindfolded? Maybe for the grand rain ritual mages like her had to be stuffed with energy or smth and it blinded them, maybe they became blind after the ritual. But one thing for sure, the Ice Stone came as a byproduct of the ritual, not as the goal. And it clearly was something unforseen seeing how mages fumbled with its properties to learn what use it can bring.

The Ice Stone can also change its properties, so it may be in whatever form in Mu-Deok's body. But this stone definitely is the answer as to why Naksu's soul shifting turned out so different - why there's no mark, why she still hasn't petrified with no energy, etc.

As for soul ejectors - it may be that the current royal family has a stash of premade ones from the old times. And the queen smuggles them to the villain through soul shifted servants.

I saw a good theory below about how Mu-Deok opened the Jin vault not because she's Jin clan's eldest daughter, but because the Ice Stone, the one which not only is involved in creating soul ejectors, but also all the artifacts, is inside her body. Meaning she can be sort of like the master key to the vault.
The plot will probably go Jin clan's daughter way, because it's a k-drama and in k-dramas big coincidences happen all the time. But still, I find this theory compelling.

It's inside of her somehow.

It was said earlier that bodies must be compatible for it to be successful. Clearly male into male is more compatible.

Yea, but you know how jealous SFLs in k-dramas are. They just don't give up :)

Yea, but FL's colleague with whom she studied in the university also seems to like ML. So it may be a love triangle still, but in another direction.

But Uk likes Naksu person, not Mu-Deok. I think you’re just having a SML syndrome.

He said he recalled her ears. So Jin daughter it was.

I wouldn't put much stock into it. Probably a working title or mistranslation from Korean. You can even read it in the synopsis here: "hwanhonsool" - the soul of the dead return to the living. Does this term mean return, or alchemy of souls, or whatever else is known only to native Koreans.

Artifacts were saying that the Ice Stone is inside Mu-Deok's body. That past scene with the mage and the blind maiden is unclear. Was it even the same mage? Just two silouettes. But the blind maiden was involved in the grand rain summoning ritual. And also somehow involved with the Ice Stone. Probably why Mu-Deok was blind in the past and went blind after leaving he vault - something involving magic is happening with her eyes.

Yea, the guy was clearly upset and disappointed with her, he figured out she was lying about the jade. But it's how it usually goes with SFLs being bitches to FLs because of jealousy. Let's hope she'll start seeing Dangu in a different light soon.

Girl is a total brat. I especially found it jarring how she said she will sell Mu-Deok and then closed the doors to the vault and left her to die just to cover an inconvenient lie. But I suppose with her mother being a cold-hearted bitch as well it's not surprising how she turned out to be.

But hey, I think when it will be revealed that Mu-Deok is the lost daughter she will have a host of suitors. Maybe even the Crown Prince, since he pines for her as well.

I really don't like it when writers can't contain the story even within a generous amount of episodes. I really hope this season has self-contained story. I really hate waiting years for new seasons to come, which also is not a given that they will air.

The villain already did suggest that to Jin mother. But suggested it be the younger daughter, not the elder, otherwise crown prince will have to go to the Jin clan, which his family won't allow.

What about team Naksu? Girl had it rough all her life too. I'm rooting for both leads to have a happy ending, not the sad or cliffhanger one.

I found it funny too, especially how confident and calm he was while roasting them. SMLs have no chances with him around.

Ice stone is inside Mu-Deok's body, but it she's her own person with a soul. And her soul is still inside her body, it was already shown in the previous episode.

Reincarnation is overused in k-dramas. I hope there is none in this one.