The First Magic Duel

"Loser has to forfeit all of their power."

I have this theory about the alicorn amulet and how it was created...
Edit: asked for some more information, and i guess some of it does need explaining. In my head I imagined a scenario where Celestia meets another alicorn threatening to rule equestria as well, on the basis that he's also an alicorn and that makes him a perfect candidate.
"Just because you're an alicorn you think you're royalty? what does that make me?"
The only way he could get rid of Celestia was to take her magic away somehow. He planned on terrorizing the country until she agreed to duel him, hence "Loser has to forfeit all of their power."
Even though they're magic is nearly equally powerful, Celestia wins the duel and the alicorn is forced to give up his magic and create the alicorn amulet which his power now resides. But with a catch, he cursed the amulet so anyone who wears it becomes more and more corrupt. Ensuring that his magic can't be used for good.

_{There's also an alternate story where Celestia loses the duel and Luna has to win her magic back, but then this is all just an idea}

Oh and by the way, this screenshot is fake.
I had to make my own hub logo and everything...

~Sandbag