If it seems like it's cheating to bunch a handful of games together in one entry... well, it kind of is. There are a number of other Final Fantasy games that I would consider to be "gems," but each of them was chosen for some very specific aspect. Final Fantasy IV, VI, and VII are probably the least radical of the modern entries -- and therefore, the least unique -- yet they're considered to be the most beloved entries in the series.
Final Fantasy has always walked the very thin line between "casual" and "hardcore" gaming styles. The idea is that casual gamers will be attracted to the narrative and characters, while the hardcore will find some crazy customization or battle aspect to figure out.
Some of them tilt in one direction more than the others -- Final Fantasy V, VIII and XII offer hardcore gameplay systems, while Final Fantasy X emphasizes story. These three entries -- IV, VI, and VII are the most balanced between the two aspects, which is probably why they're so widely pleasing.
Final Fantasy IV is the epitome of cheesy, melodramatic 16-bit RPGs -- the dialogue is brief, the characters are likable but one-dimensional, nearly half of the game's cast nobly sacrifices themselves, and all but one of them turns up alive and well later in the plot.
The story of the conflicted Cecil and his equally conflicted best friend Kain has all of the basic workings of a Shakespeare drama, even if they're carried out with silly little sprites, whose only methods of emotional expression include spinning, bouncing, and looking at the floor.
Some of the 8-bit RPGs began to emphasize narrative, like Final Fantasy II's war-torn plot or Dragon Quest IV's party of memorable warriors, but Final Fantasy IV weaved everything together brilliantly and set the stage for all future genre entries.
As such, the advent of the SNES signified not only enhanced graphics and stunning music -- Final Fantasy IV still has one of composer Nobuo Uematsu's best scores -- but the next generation of storytelling as well. The fact that that the DS remake -- released fifteen years after the original -- still stands up to most other portable RPGs is a testament to its lasting power.
Final Fantasy VI was released four years later, with significantly improved graphics. Characters were now twice as big, and potentially twice as expressive. The themes are common, especially throughout the Final Fantasy series -- a rebellion against an evil empire, an outsider with mysterious magical powers, and a sadistic villain that seems to be evil for the vaguest of reasons.
Final Fantasy VI's strengths lie in both its scenario and its characters. It has the largest group of playable characters in a Final Fantasy game, with a total of fourteen party members, including two hidden ones. Their abilities are static, like FFIV and unlike FFV. They're still marginally customizable, through the use of relics and equippable summon monsters called Espers, which modify their stat growth a bit and teach them magic.
Each character's inherent skills are important from a storytelling standpoint, as each of their personalities are reflected in their abilities. Cyan's "Bushido" requires waiting several seconds to charge up attacks, which reflects his persona as patient and stoic warrior. Sabin, while not having a particularly strong personality, is occasionally represented as a bit of a meathead.
As such, his attacks are incredibly powerful, as denoted by his muscular stature -- but they're unpredictable, seeing as how you can't target individual foes, and the success of a move is determined by command motions, the fighting game equivalent of brute force, rather than strategy. Setzer doesn't require much of an explanation -- when you convince him to join your party, his response is basically "Why the hell not?" He's a man on the edge, just like his Slot machine ability, which, if luck isn't on your side, can potentially harm your own party.
This idea of portraying a character through gameplay has been around for ages -- strong characters use physical attacks, frail characters use magic and have low HP, etc. It was also used in the same manner in Final Fantasy IV -- Cecil's life-draining attack as a Dark Knight, which are replaced with healing powers once he becomes a Paladin; Edward's Hide attack showing his cowardice -- but they're much more expanded here, and a quite bit more interesting.
Like Chrono Trigger, Final Fantasy VI's other strength shows through in its remarkably powerful scenario design. Once the game really gets into gear within the first hour or two, the game tosses out a number of memorable events -- the spooky Phantom Train, the introduction of Kefka and his malicious poisoning of Doma Castle, the silly but ultimately impressive opera scene, the assault on the Magitech Factory, Celes' attempted suicide.
It's also one of the first RPGs where the bad guy actually wins, enslaving the world and reducing it to a total wasteland. It's also worth pointing to the second half of the game -- where the narrative steps aside and eventually lets you explore the open world. Though disliked by some series fans, it also shines, as a huge number of subquests open up, allowing those suffocated by the linearity of the first half to get a little more breathing room.
And then there's Final Fantasy VII, beloved for its interesting characters and cool cutscenes, hated mostly for being a huge success -- and thus the effect it had on JRPG design. And yet, FFVII rides heavily on the coattails of its predecessor -- a group of rebels banding together to face an oppressive evil, another young girl with ancient, mysterious powers -- but goes so over-the-top that it stands out from the crowd.
The biggest difference is that FFVI was an ensemble cast, with the viewpoint switching around between a handful of major characters. Instead, FFVII focused on the development of Cloud, whose huge, spiky blond hair and exaggerated sword has since became an icon of Japanese excess in the same way that hulking, bald space marine has become stereotypical Western gaming.
Cloud is neither hero nor anti-hero -- as we learn, Cloud is somewhat of a weakling with delusions of grandeur, believing himself to be a world-saving bad guy when he's actually just a dude with some psychological issues. This is one of the first instances of an unreliable narrator in JRPGs, adding something new to the usual "boy meets girl then saves world" formula.
At the time, its impressive cinematics were Final Fantasy VII's selling point. The character development system isn't quite as cool this time around -- the Materia is similar to the Espers from FFVI, except it allows characters to swap skills amongst each other.
By removing most of the specialized character skills, it loses some of the narrative appeal of its predecessor, and thus the player tends to pick party members based off who looks the coolest, rather than what they can do. Outside of a few famous scenes -- particular Aeris' murder -- the game is muddled with a subpar localization, another step down from FFVI.
However, the game world has been fleshed out favorably. FFVI's world drew elements from steampunk, but was really just a darker, more detailed variation on the previous games. FFVII's field may just appear to be a 3D rendering the same world map we're used to, but the locations are hugely varied, ranging from the creepy European village of Nibelheim, the Disney World-esque amusement park Golden Saucer, and the traditional Japanese town of Wutai. At the core of this is Midgar, a technological dystopia that borrows heavily from Blade Runner and other classics of science fiction.
It's easy to point fingers at Square Enix for abusing the Final Fantasy VII series with its multiple spin-offs, like the lousy shooter Dirge of Cerberus or the flashy action flick Advent Children.
But the world is so rich and interesting that it actually feels like it has enough depth to explore and expand. The best spinoff -- Crisis Core for the PSP -- draws heavily on the player's nostalgia for Final Fantasy VII, so wandering through Midgar feels like revisiting an old friend. Despite its over-baked tendencies, it still remains compelling, even after the twists have long worn out their appeal.