Bat Ponies

Ah, the Bat Pony. A fan favourite despite the fact that they appeared for a total of like three minutes and were never explained.

They always appear as Luna's or Nightmare Moon's guards. They have tufted ears, bat wings and slit pupils, and not even staff members would give a solid explanation as to what they were. There was a fairly common theory that they were just pegasi altered by Luna's magic, for the aesthetic I guess?

The second appearance of Bat Ponies in the show didn't help. In the timeline where Nightmare Moon takes over, she has Bat Pony guards but also a bat-winged Rainbow Dash. So the theory was true, it's a magic thing. But then all the other guards have the tufted ears and slit pupils, which even bat Rainbow doesn't, so, they're both a separate species and a magic thing? I don't think even the writers knew. Oh well. The Bat Ponies we see have grey, blue or purple coats, and the stallions are larger and stockier than the mares, though those could just be the common body types for guards.

Fluttershy gets turned into a Vampire Bat Pony that eats fruit as a result of a mishap with Twilight's magic. They do not seem to be a natural occurance.

To my great disappointment, a leaked G5 production document reveals that Bat Ponies could have potentially appeared as a proper species had Make Your Mark gotten more seasons. They are described as being goth, spooky, having dark colours, and living in a place called the Darklands. RiP to the coolest idea we will never get.