FFIV: Those creepy doll things.
FFVI: Kefka's laugh [just kidding]. Kefka's Nihilistic philosophy. Kefka in general when he's not being hilarious.
FFVII: Everything to do with Jenova, running around ShinRa HQ when there's blood everywhere and an eerie silence, Nibelheim and everything that happened there, everything that Vincent went through at the hands of Hojo, Hojo in general,
ACC: Jenova looks even scarier in the movie. Also the fact that for most of the movie, several characters are carrying her severed head around in a box is genuinely frightening and...eeww! Also, geostigma.
FFVIII: Faceless Squall.
FFIX: Necron, Kuja's Villainous Breakdown, and the poor Black Mages...
FFX: Yunalesca, Anima, and the whole concept of Summoners and the Pilgrimages.
The series as a whole: Tonberries and Malboros.
Your turn!
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Quote:
A memory is something that has to be consciously recalled, right? That's why sometimes it can be mistaken and a different thing. But it's different from a memory locked deep within your heart. Words aren't the only way to tell someone how you feel.” Tifa Lockheart, Final Fantasy VII