Does it ever say anywhere that his difficult choice will be between the two nations, or is that just assumed?
I'm kinda new to the fandom and everything I've learned about Kaeya so fast is kinda scaring me with the death flags. Like, most fictions (and people, unless they're suicidal) would classify choosing to sacrifice yourself a difficult decision (not because it's not clear to make, but because is just a hard thing to do?) So, I'm kinda scared I'll have my favorite character dying on me yet again (I swear it always happens to me). Please hoyo don't kill my sweet blue pirate wanna be.
Hi anon, welcome to the fandom!! I'm so glad you asked!
The first time we hear about Kaeya's "choice" is in his Vision story that goes as follows:
If Khaenri'ah and Mondstadt went to war, which side should he support? To whom should he offer his assistance: his birth father, who had ruthlessly abandoned him? Or his adoptive father, who had loved him and raised him?
For the longest time, Kaeya had agonized over these impossible questions, caught between the opposing demands of loyalty and duty, faced with an impossible choice between truth and happiness.
The second time was Mona's voice line, which isn't as explicit, I suppose.
Then we've got his Hang-out Event. In big short (bc I don't want to spoil too much in case you aren't there yet!), there's a character that parallels Kaeya and they have to choose between two nations as well.
So yes, most sources point rather firmly to a choice between two nations. That said, I believe Kaeya's conflict is as much about the nations themselves as what they represent, as he himself says in the Vision story.
Mondstadt stands for his family, friends and all the love he recieved there. It's warm summers, azure waters, grapevines and crystalfilies glimmering in the sun. A fairy tale, really, compared to Khaenri'ah.
Khaenri'ah itself is the harsh reality, the many terrible truths about Teyvat. Celestia's constant surveilance. The Abyss and corruption, ever encroaching. A cautionary tale against ambition.
To choose Mondstadt is to turn a blind eye to the horrors his people faced and are still facing. To pretend that sunshine world of knights and gods and Visions is simple and kind. It's to abandon those who still suffer at the hands of Teyvat's occupant.
And to choose Khaenri'ah is to leave all of this, his happiness, and himself behind. He'd turn away from the sun and venture back into the shadows. As Khaenri'ah's Last Hope, he would face the dark truth of this world head on and challenge it, at the price of his spot by the side of everything he holds dear.
(Well, in theory, anyway. I don't believe choosing to help Khaenri'ah would dissuade, say, Jean from at least trying to understand his perspective. But you know what I mean, yeah?)
("Challenging the truths of this world" is still on his radar, of course, I just hope he gets to do it with his friends and family by his side :3)
If you want to know my perspective, it's true Kaeya has a lot of deathflags, but I'm not too worried! Genshin writers have been skillfully avoiding killing any playable characters. While it would be possible (in my opinion) to make Kaeya's death a satisfing ending, I don't believe that's the kind of story they want to tell! Of course there always has to be a first time, so he's not 100% safe, I suppose, it's probably too early to worry <3
I'd definitelly recommend taking it slow with all the lore crumbs! There's so much to learn and it can get overwhelming.
Again, thank you so much for asking!! If there's anything else at all you'd like to know or that you'd like me to elaborate on, let me know pretty please! I love talking about Kaeya and Khaenri'ah and Teyvat lore so so so much <3