After being sent to Ponyville, Twilight discovers all about its inhabitants and the "rulers" of it. She falls under their possession and becomes their agent of chaos as they steal evil's magic for themselves.
Updates: 1st of the month
(To be clear cuz there's some icky stuff happening in this comic, all characters are considered to be 18 or older in this canon. I wouldn't want to put any underage characters in a story like this one.)