The Bu Yeon soul that entered the baby (13 months in the womb, already dead) was not Bu Yeon herself instead the first blind Jin mage who summoned the Lake / ice stone over 200 years ago?
It could be why she tried to return, or destroy, the ice stone when Jin Moo kidnapped her.
If she's that mage, then it explains why the body can contain two souls, she's a very powerful mage after all.
-She's probably using her immense energy and spells no one else know to ensure her soul and Nak Su's doesn't destroy the body. - She probably knew how to keep two souls inside instead of expelling each other. - She also knew how to cleanse the energy when using the siphoning technique.
If this is the case, would it not be so that the soul who brought down the Lake and the ice stone is the only one who can destroy or return it back to the heavens?
There were other blind Jin members but none were as powerful.
But why Nak Su?
It is not possible that Nak Su's soul was the original "Bu Yeon" soul. Nak Su is older than Bu Yeon and Jang Uk. She was already a young kid when Bu Yeon and Jang Uk were conceived.
So, why Nak Su?
As it currently stands, the "Bu Yeon / Mu Deok" body is practically Nak Su's. Once the blind girl leaves the body, it is 100% Nak Su's body, and since the blood in that body is of the Jin, she is as much as a Jin mage too and the gate of the vault will open for her regardless. (She probably have to learn the Jin spells of course.)
In the end, we get the Crown Prince as the new king. Jang Uk as his right-hand man. Jang Uk married to Nak Su.
1. Jin Bu Yeon - it was Jin Moo who was with her and it was only the two of them - Jin Moo suspected Bu Yeon tried to make the ice stone disappear - Jin Moo pushed her to the river (he probably assumed she drowned)
2. The ceiling on the constellation recorder room can only be opened by the energy of a constellation recorder mage. - Nak Su is definitely the daughter because the basin and roof reacted to her. - She is connected to the Lake (and the basin). - Nak Su thinkgs the Mirror broke because of her own power. - The unused ice stone energy was reacting to her (and possibly to Bu Yeon) = lightning strike.
3. After the lightning strike, the "Mu Deok" body lost her sight. - Nak Su said it was like after she came out of the mirror. - The power of the ice stone possibly boosted the energy of Bu Yeon (she's an energy master).
1 
The episode explained it later that she had a major sensory overload which led to her sudden meltdown.
1. His daughter is now relying on someone else
2. It will be very hard to tell her the option to go to the States and get autism support there
Perfect tag line. =))
It could be why she tried to return, or destroy, the ice stone when Jin Moo kidnapped her.
If she's that mage, then it explains why the body can contain two souls, she's a very powerful mage after all.
-She's probably using her immense energy and spells no one else know to ensure her soul and Nak Su's doesn't destroy the body.
- She probably knew how to keep two souls inside instead of expelling each other.
- She also knew how to cleanse the energy when using the siphoning technique.
If this is the case, would it not be so that the soul who brought down the Lake and the ice stone is the only one who can destroy or return it back to the heavens?
There were other blind Jin members but none were as powerful.
But why Nak Su?
It is not possible that Nak Su's soul was the original "Bu Yeon" soul. Nak Su is older than Bu Yeon and Jang Uk. She was already a young kid when Bu Yeon and Jang Uk were conceived.
So, why Nak Su?
As it currently stands, the "Bu Yeon / Mu Deok" body is practically Nak Su's. Once the blind girl leaves the body, it is 100% Nak Su's body, and since the blood in that body is of the Jin, she is as much as a Jin mage too and the gate of the vault will open for her regardless. (She probably have to learn the Jin spells of course.)
In the end, we get the Crown Prince as the new king. Jang Uk as his right-hand man. Jang Uk married to Nak Su.
Indeed, how can one live more than a hundred years? Even trained by the founder of Songrim when he lived 200 years ago during the great mage war?
I can't stop laughing, and it only gets more hilarious every new episode.
- it was Jin Moo who was with her and it was only the two of them
- Jin Moo suspected Bu Yeon tried to make the ice stone disappear
- Jin Moo pushed her to the river (he probably assumed she drowned)
2. The ceiling on the constellation recorder room can only be opened by the energy of a constellation recorder mage.
- Nak Su is definitely the daughter because the basin and roof reacted to her.
- She is connected to the Lake (and the basin).
- Nak Su thinkgs the Mirror broke because of her own power.
- The unused ice stone energy was reacting to her (and possibly to Bu Yeon) = lightning strike.
3. After the lightning strike, the "Mu Deok" body lost her sight.
- Nak Su said it was like after she came out of the mirror.
- The power of the ice stone possibly boosted the energy of Bu Yeon (she's an energy master).
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