I would have to say between IV, VI, or IX.
I loved the characters of IV and its awesome soundtrack.
VI is just a masterpiece of a final fantasy game. Still love beating Phantom Train with just a Phoenix Down each and every time as well.
IX I give credit due to it being the first FF I ever played, and the fact that it's a bit underrated IMO. The Trance feature irritated me a bit though in the game. Why banking and saving it for boss fights was out of the question is beyond me.
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Okay people, bring me a spatula, some tanks, and an anenome! Sh*t's gettin' real tonight!
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