Happy Nightmare Night!
Credit to Cygne on Soundcloud for the vocals

Lyrics:

Tis a somber night in ponyville
The sky is clear the moon is bright and still
Little fillies coming out for fun
But they be laughing when its done

Nightmare Night, what a fright
Give me something good to bite
see us come, see us go
see our scary costume show

trick or treat, look at me
fill my basket up with sweets
please oh please, say no or
Nightmare moon will devour my soul

Here she comes

You escape the curse of Nightmare moon
beware you foals, coming very soon.
Nightmare moon demands a sacrifice
with your candy you must pay the price