Heaven's Wing

"WE MUST FIND OUT THE ISSUE!" shouted Twilight Sparkle in the Royal Canterlot Voice.

"Detection spell," said Trixie. "I'm on it." At this point, the blue mare was too confuzzled to continue her third person stage persona. "Ancient curse," she droned.

Twilight nodded. "I'm going to look for clues. When I find something, I'll notify you via magical current. Then, please find a book on the subject." She noticed something gleaming in the grass and endeavored to give it a look. "And be fast." Trixie was somewhat offended by the lavender alicorn's terseness, but put her feeling away for the sake of efficiency.

As Trixie teleported away, Twilight looked at what was in the grass. Golden spoon. What can you find?
...

...

...Curse of the Golden Spoon. Any who unearths it will unleash a crippling plague. Can be identified by cuneiform on the handle.

Twilight shook her head, sending a message to Trixie that told her that it wasn't it. She continued looking, but had nothing. For hours, she sorted for junk, occasionally finding something before quickly discarding it. As the sun descended in the sky, Twilight remembered something that she had grasped with her magic the night before. Trixie, I think I found it. Go into Celestia's book of spells she put a failsafe on, the one with the fancy scribbles about how celestial bodies still need to move around when princesses are in compromising positions. Golden Feather.
Trixie quickly found the tome before looking through the sections. "Mmm, no, not that, THERE'S A SPELL FOR THAT I THINK I'M GOING TO BE SICK, no, not that, oh here." Golden Feather. When a time travel spell goes awry, nobody can ever die. Make them freeze into place, stay in a single space. Yadda yadda yadda, Everything twelfth feather Philomena drops turns into a hawk but occasionally a magically connected pony... Hawks drop Feathers of Gold. Yes. Twilight, we've got it. Also it spreads outside of the city of origin pretty darn fast, so watch out.

Twilight disliked the way Trixie skipped over information, but took what she had anyway. Now to find the cure.