The Conversion Bureau: The Dead.

"Are you sure this will work, Sister?" Luna asked Celestia.

"Of course, Luna. We will arrive on Earth and wash all the dirt and evil from Humanity," replied Celestia. Little did she know that Fate would decide to throw a curve ball. "The spell is almost ready and the potion is prepared."

Equestria, mainly Celestia, saw a vision of Earth and Humanity. They decided to help Humanity better themselves. As Celestia and Luna charged the spell, the throne room they were in grew hot and dense. Just as the spell reached it's apex, a mite of dust flew in on the winds created by the spell to Celestia's eyes. As the evil speck of dirt irritated the eye's of the sun goddess, she lost some of her concentration. This allowed them to punch a hole through reality, find Earth, but "select" a different one.

The rest of the plan went off without a hitch. Equestria appeared off the east coast of what the Humans call "North America" (Celestia would have to change the name after Mankind has been freed). Or so it would seem. The Sisters immediately sensed something was off.

As Celestia and Luna went to one of the balconies, Celestia told Luna what happened with the dust.

Luna shrugged as they made it to their destination, and looked at the new sky. "I wouldn't worry about it, Tia."

Celestia nodded and looked at the cloudy sky. "Something just feels off though."

Luna frowned. "I wouldn't worry about it though. Get up the barrier while I send out a scouting party."

Celestia nodded and lit up her horn while Luna left to arrange the party. Celesia smiled just a bit too widely as she thought how the Humans would like their new lives as ponies.