Ooooooo, I wanna play!!
FFI - Grew up on this game for NES. Love it to pieces. Beaten it a handful of times on NES and PSX.
FFII - Played it briefly on PSX when it first came out, beat it on NES with an emulator and translated ROM. Leveling system is terrible, and the final castle would be WAY too hard without save-states (almost every battle is with an enemy that instantly kills). Probably my least favorite.
FFIII - Beat it recently on NES with an emulator and translated ROM. Really fun game, loved the job system and the story was pretty good. Again, the final castle is way too hard, and would probably give me fits without save-states.
FFIV - Beat this on PSX. I felt underpowered throughout most of the game as the PSX version is 'hard-type' compared to the SNES version. Got to the final boss at Lvl 70 and lasted two rounds. Had to grind to 80 in order to beat him. So that was really frustrating. Other than that, it's not a terrible game. I liked having 5 characters, even though you never get to choose them.
FFV - One of my favorites. Beat this on PSX. Great job system, really perfected what they tried to do in FF3. Yeah, the story kinda blows, but the gameplay more than makes up for it.
FFVI - Nostalgia plays a big role for with this one, but I still feel it's Top 3. Story is unreal. Gameplay is unreal (albeit, a bit easy thanks to the Esper system). Beaten it many times on SNES and PSX.
FFVII - Never got the hype for this one. And never got past the first disc until recently. First disc drags big time. Materia system is not my favorite. I will say the game picks up big time on disc two. Beat it once.
FFVIII - Beat this recently. I really enjoyed it. I loved farming all the spells so I could make my characters stronger. every time I found a new spell was like Christmas haha. Anyway, the story was a bit convoluted and kinda reminded me of Chrono Cross... it was that confusing! But probably has my favorite end boss fight and ending of all the Final Fantasies.
FFIX - Fun throwback game. Beat this on PS3 (PSX Classic). I liked how you got abilited from weapons and armor in this one. And yes, the callback to the earlier games was a lot of fun. Probably my favorite of the PSX trilogy, although it's very close with FF8.
FFX - Played/Beat the HD version on PS3. Very linear, but that's okay. Loved the fighting engine, where you had access to all your characters at any time. But, for some reason, I wasn't a huge fan of this game. Too much story? Too much fighting? I can't recall at this point. Something didn't sit well with me though. OH. And fuck Chocobo racing in this game. Just... okay?
FFXI - Never played and most likely never will. Back when this first came out I had neither a PS2 or a desire to ever play an MMO.
FFXII - Only played this briefly. Will play the HD remake when that happens.
FFXIII - Easily my favorite Final Fantasy game. First one I had played since FF7 at the time, and only third I had ever beaten (I have since gone back and played and beaten the rest of the above). It took 180 hours, but I platinum'd this game, and also both it's sequels since. Loved the fast paced fights, loved the hunts and the end of the game, loved the story, the characters, EVERYTHING.
FFXIV - Honestly, this was a great game. This is the only MMO I've ever played, and probably won't play another one unless it's FF. But it was fun while it lasted. It was cool to see the job system from FF3&5 make a return, and it was really cool how it was utilized. But once I beat the main campaign, I could fathom spending money every month for endgame content. Just not my bag. Make it free to play and I'm there all day.
FFXV - Loving it so far. Feels very fresh. Almost feel overwhelmed since I've played 18 hours or so and am still on Chapter 3, haha. I love doing side-quests. This will be fun for a long time.
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Also wanted to slip into the conversation the rumors about the 30th Anniversary next year. Apparently all these games are coming to PS4 some time in 2017:
Final Fantasy 30th Anniversary Collection (FF1-9, including official NES translations of 2&3 for the very first time, and 2 versions of each game from 1-6 - original and most recent)
Final Fantasy VII Remake (Episode One)
Final Fantasy XII HD: The Zodiac Age
Final Fantasy XIII Trilogy
All this came from a simple google search, but there's a lot of rumors, and I love every single one.