
Misteltein, mistletoe and the power of life
Intro
Let me start off by saying I really want Mistiltein to have something cool to do with Thrain and taking down Phanes. I'm aware people often link Mistiltein with the event predating Ragnarok involving Loki tricking Höðr (Hodr) into throwing the one thing that could kill his brother Baldur which is mistletoe. Interestingly too the Primordial one aka Phanes is the name of a god of light from Greek Mythology. So he's a god of light just like Baldur. Moreover the brother who kills him Höðr (Hodr) is associated with darkness and winter (I mean come on Capitano has black ice and a void face.)
Technically Mistiltein the sword is Thrain's weapon from Hrómundar saga Gripssonar. It's not the same thing as the mistletoe that kills Baldr which is described as a dart or arrow. I believe Mistiltein is old Norse for Mistletoe so I guess it can connect to both myths or perhaps its more than one weapon.
So the theories about the Tsaritsa's polearm weapon that appears to have Naberius (Shade of life powers) tied to it presumably gifted by Rhinedotter (Gold) is what this Mistiltein Columbina mentions, makes a degree of sense. A weapon of life being the only way to kill the goddess of death.
But wait.....Thrain might still be relavent regardless of its HIS weapon or the Tsaritsa's anyway.
Hoyo may have specifically chosen to refer to it as Mistiltein instead of mistletoe for an additional reason that still connects it to Thrain even it doesnt turn out to be his weapon.
#Additional context about Myth Thrain
Fun but not so fun fact about Myth Thrain. Mistiltein is the name of his former weapon. Draugr/king/sorcerer Thrain, once weilded it and slayed 420 men and then later retired to a borough with his sword and riches. Eventually he turned into a undead creature called a draugr and is described as black and blue with cat like claws.
A man named Hrómundar stole Thrain's weapon "Mistiltein" killed him and then burned him to ashes so he couldnt regenerate. So basically Thrain was killed by Mistiltein.
#My 3 possible theories*
1.If Mistiltein in Genshin is Tsaritsa's spear imbued with the power of life it could play a role in ending or altering the curse of immortality. What Capitano calls the curse of absolute life. I'm not saying that Ronova's death would undo the curse just like that, nor would it be a good story if all the immortal Khaenri'ahns suddenly dropped dead and thats it. Rather it could be used to alter or reset the effects it had on Khaenri'ahns. Like an undo, revert, or rebirth button. Gold and the Tsaritsa could've decided to join forces since they both have possible personal reasons for it (a sinner trying to right her wrongs/ a mother of a possible Khaenri'ahn and close friend of Khaenri'ahns trying to give them a second chance) using Naberius's power of life.
In this way Genshin's Thrain is also killed by Mistiltein but he rekindles in the flames because he had to truly die (be rid of the curse) in order to truly live again. That and I think death and rebirth is a common theme in the Fatui both literally and figuratively. I think it has something to do with transcendence like the trailer title. It may even allow for the chance to become a descender or at least someone who cant be effected by the rules of Teyvat like most.
Mistiltein could be Capitano's weapon used to kill Phanes, and they're combining myths but subverting Thrain's death (he lives on, comes out of the enternal flame rather than being damned by one and takes the role of Hoor (winter/darkness god). I mean Capitano is already a subversion of the Comedia dell'arte's Capitano and Genshin Thrain is basically the opposite of myth Thrain so he gets the right to be reborn instead of being denied it.
What I said in 2 except he's killing or upsurping Ronova not Phanes. Kind of funny that she won't allow him to die and that would actually give him a huge advantage coupled with weilding the one weapon that could kill her. He did say the following -
>"Your curse in now the tool with which I will overturn the oppression of the gods."
Frankly Hoyoverse can pick and choose which parts of the myths they want to refrence or subvert but these are some scenarios that came to mind.
#Bonus
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Mistletoe - significance (tied to life)
Was considered a heal all to druids
Known to grow berries and leaves in bunches of three (trinity) used for Christmas.
Associated with Love (Capitano's got a golden heart, the Tsaritsa's ideal is love.
Interperated by some to be the golden bough allowing safe passage in the underworld in the classic Aenid.
Golden bough in genshin is a branch of irminsul - see - https://genshin-impact.fandom.com/wiki/Golden_Frostbound_Oath
Sources -
https://www.odins-gift.com/poth/2stories/thestoryofthemistletoe.htm
https://www.germanicmythology.com/FORNALDARSAGAS/HromundarSagaGripssonChapell.html