How so...? The FF games are barely even a series...Most of the time I feel like the only thing actually connecting the games are Easter eggs for the fans...OMG there's a chocobo in that dude's fro! What were we talking about?!
Yeah, but there's a lot of fundamental similarities, globally and by platform. 4, 5, 6 were more similar to each other than 7, 8, and 9, and 10 was just WEIRD! 12 was also a bit different but essentially the same.
The main character(who uses a sword, always) goes on a journey, meets people, gets a boat, meets some more people, kills a few bosses, gets an air ship, goes to an island you can't get to by boat, goes to an island you're not supposed to go to until the end of the game(at least how I play it) and then you fight the final boss, who you find out who it is by the end of the second disk/major plot point.
There's always some nobility character, some brooding, mysterious character(five may be the exception) and a love interest. The main character(who always uses a sword, remember) always has some deep mental/emotional/psychological problem:
Cecil(I have to kill people), Leena(my dad's dead and I don't know how to rule), Terra(I don't know what love is!), Cloud(Oh, God, where do I begin?), Squall(I'm always so alone), and Zi-Actually, despite being the one who really deserves the emo attitude, he's pretty upbeat. Tidus and Vaan followed after Zidane in this respect, but then again, they're weird.
6 and 7 are incredibly similar. I remember about a year ago, my older bro was doing a replaythrough of FF7 and I would keep pointing out things going "Oop, that looks just like something from FF6," or "Ooop, that dialog sounds like FF6." The stairs to the Magi Tower in 6 and the Shinra Building in 7 are identical. This really doesn't say much, but it's interesting.
Square's been trying to take FF in a different direction since 10, and has met with varied results. 10 set a new mold, and 12 completely shattered that one. 13 is just another wave of that. Still, I doubt they'll ever get completely away from the fundamental stuff that makes an FF game an FF game.
