FFI - Black Mage
FFII - Everyone
FFIII - Dunno
FFIV - The Elder and the other three fiends besides Rubicant.
FFV - Everyone, FFV was a horrible step down in its character development compared to one game ago.
FFVI - Umaro
FFVII - Everyone except Cloud, Tifa, and Aerith. >_>
FFVIII - Cid
FFIX - Fratley and Lani
FFX - The blitzball players(all of them, except Tidus and Wakka)