My favorite By Far is "You can hear the cry of the Planet" from Final Fantasy VII.

Final Fantasy VI - Overworld (World of Balance)

How could it not be?

Crisis Core - Price of Freedom

Takeharu Ishimoto >> Uematsu

Price of freedom, crisis core

Final Fantasy 7 - Sending a dream into space

Too many excelent songs to pick one. I think itd be something amongst "The Place Ill Return Someday", "Aeriths Theme" , "One Winged Angel", "The Extreme" , Battle on the Big Bridge FF XII version (I prefer it over the original), "Cloud of Darkness" , "Fighting Fate", "Blinded by Light" (I love Uematsu but this is the best normal battle song ever, and Im not talking about FF games only here) or "To Zanarkand".

Yeah, this song right here. Pretty sure it's canon:

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Everyone should listen this:
FF IV - Faraway home town.
And Roaming sheep.

The Zankarkand one.