Originally Posted by Kawaii Ryűkishi
I'll say FFV. It has the only ending whose events can be altered by actions taken in the game besides FFIX (and to a much larger degree than that). It also has probably the best ending music in the series, from "The Silend Beyond" to "Final Fantasy" (you know, "Prologue") to "The New Origin." It's just great when that last one gets to its most triumphant part just as we're shown the four heroes, one after another, fighting an enemy and going into a close-up and freezing while a list of their level and the abilities they've learned scrolls by.