#2 and #4 kinda happened, albeit not ’til Season 5.
 
 
@Sixtyfour215  
Maybe they could use it as part of a plan to get at Cadance and influence the use of her powers. Chrysalis might not have had plans for her, but to a changeling with a tad more vision might have plans for a pony who can control love.

The first 4 are okay, but the rest are… slightly out there.
 
Most of the people here will probably think that last part is an understatement.

>Celestia dies
 
Screw you,OP.

should be good, if the season 4 finale, all the ponies converts to Humans

>Last One  
NO.  
FUCK YOU  
FUCK YOU  
FUCK YOU  
NO.

Last one sucks, second-to-last would be kinda OOC for Twilight even with more power than she already has but potentially interesting, everything else would be great.

“Gilda episode”  
HA!  
HA HA!  
HAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA  
WHY THE FUCK WOULD THEY DO THAT WHEN THEY CAN JUST FILL THE SEASON WITH MORE UNFUNNY, UNCREATIVE, BORDERLINE UNWATCHABLE CMC AND SPIKE EPISODES?  
YOU A FUNNY GUY.

I like the Silver Spoon idea.

I liked, especially the Sombra part and except the Celestia part.

last one made me laugh

This whole thing is wrong, wrong and wrong.  
Denied.

That last one sucks.

@Randomosaur
 
Certainly, in our universe. Maybe star evolution goes different in Equestria.

@smashfan666  
But the Crystals would generate misery.

@sixtyfour215  
actually, they could generate a crystal barrier to prevent escape, and heavily guard the only way in or out of Canterlot.

@Dr. Robotnik  
Meh, they don’t seem to be very bright.  
Also, Misery doesn’t kill you. Ponies could trek through the crystals to escape easily.

@sixtyfour215
 
Unless of course, they were to farm love by trapping their “cattle” in one place, via making all but one area a wasteland of misery.

@ZORDON
 
She will live until the Sun becomes white dwarf, then.

Good ideas, except the last one. My headcanon is that Celestia’s lifespan is determined by her sun, so she may live for millions of years. And, like a phoenix, if the sun burns out, it reignites shortly thereafter.
 
Look, there’s a better idea. Celestia is ill, and everyone fusses about it. She dies, and the sun with her. Tartarus breaks loose, and they have to defend themselves until Celestia is reborn. That’s why they need an extra alicorn. To help defend.
 
That could be a nice two parter.

Eh, I don’t think the Changelings using Sombra’s horn to generate Dark Crystals is smart on their part. Sombra created misery, which is the antithesis of love. It’d be asinine for them to use it.

Why would Celestia need a replacement? Luna can turn day and night herself, and unicorns as a group can handle it.

All but that last one, I would watch.

This could actually work.

You forgot one: The surprise tweest ending