So Final Fantasy has a proud tradition of having you start off by fighting some giant, oppressive regime only to have it fold or became irrelevant at some point so THE REAL villain can take center stage.
Barton to Golbez
Gestahl to Kefka
SHinra to Sephiroth
Galbadia to Edeamecia
Alexanderia to Kuja
Cocoon Sanctum to Barthandalus. (in a really weird way)
My question to you all is this. WHich was the most vile starter? Which tyrannical force, despite not being the main target of your heroes after a while, still impressed you with its wickedness and came off as a legitimate threat?