

I might commission someone for it. Maybe Faux.
Something like this:
Twilight, in an attempt to rescue one of her friends and/or impress Princess Celestia, ends up as a super-powerful alicorn that shows everyone up and saves the day without breaking a sweat. That is, until her powers start overloading. She unintentionally starts wrecking half of Ponyville despite the best efforts of the other princesses and her friends to contain her, and ends up gravely injuring one of them in the process.
This leads to an extended action sequence where half the team tends to the wounded member and half the team enacts a plan to try and help Twilight regain control over her destructive powers. This ends with Twilight urging them to use the Elements of Harmony on her. Everyone protests, considering the effects it had on Discord and NMM, but when it looks like she’s ready to self-destruct, they’ve got no choice but to use them on her.
Twilight is fine afterwards, but bedridden. She’s still an alicorn, so the princesses had to put all kinds of magical blockers on her, and while she’s not quite going to be her magical-prodigy self for a while, she’s at least okay. She’s got touching moments with all her friends as they comfort her.
Boom. Aesop about taking things too fast, getting to see Twilight in a powerless position, potential for all sorts of future storylines where the town fears Twilight, and Hasbro gets to bake its cake and eat it too in regards to Princess Twilight.
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