It's okay if you don't know Dragalia Lost. This story introduces this franchise. Go ahead and give it a read!

And my deepest gratitude goes to Mix-up/Amalgamzaku for creating the wyrmprint (cover art) of this Dragonbound tale. (Links leads to his FIMFiction profile and DeviantArt page respectively)

It was always clear that the human dimension of Equestria was very distinct to its pony dimension. There was not a lot of magic energy save for a few places, infrastructures are different, and, well... It doesn't seem so magical...

Until they spotted a former enemy. Giving chase, Rarity, Sweetie Belle, Big McIntosh, and Flash Sentry got lost in a forest, leading them to a mysterious castle that can't be seen by any human means and inhabited by a Mysterious Owner! The girls and guys are about to learn a long-forgotten history... An era where Dragons co-existed with Humans!

A Crossover between Equestria Girls and Dragalia Lost.
Copyrights and credit go to Hasbro, Nintendo and Cygames respectively.