Nightmare Moon is best villain, period. All this “New Lunar Republic” and “I love Luna because more people love Celestia” (lol, bcoz’ of that bullshit Celestia is least loved proncess now) crap doesn’t make much sense to me (but I in fact do love NaCP’s “For the New Lunar Republic”), but NMM is seriously least liked villain and she deserves more love.
Tbh though, her evil laugh at the end of the first episode is what solidified my love of this show all those years ago and guaranteed her a permanent spot in my top 5 best ponies of all time (positions of all within shift depending on episode but she’ll always be in that list)