Breaking up the party helps us identify the characters as individuals rather than as just parts of a whole.
In Final Fantasy XIII, most of the cast is introduced in the very beginning. Rather than spread these introductions out over the course of the game like other RPGs, the cast comes together after just a few hours and then breaks up again. It’s a strange series of moments, seeing your party systematically disbanded, but the reasons behind these divisions are very personal, and as we watch each character go their separate ways, we learn a lot about their inner thoughts and desires.
First some background information on the world of Final Fantasy XIII: the game takes place in Cocoon, a protective sphere separating humanity from the dangerous outer world of Pulse. The fal’Cie are powerful magical beings that reside in Pulse. They attacked Cocoon a thousand years ago and were repelled, but the attack left humanity paranoid and forever fearful of these creatures. Adding to these fears is the ability of the fal’Cie to turn humans into servants, the l’Cie. When branded as l’Cie, you’re given a vague vision of a task that you must complete. If you’re successful, you turn into crystal; fail, and you become a monster. Either way it’s a death sentence, and one more reason to fear the fal’Cie. Yet ironically, Cocoon was built and is still maintained by these magical beings. They control everything from day and night cycles to weather patterns.
Up to this point in the game, we’ve only seen snippets of their relationship, but we’ve heard multiple expository speeches from Snow about his love. The problem with this exposition is that it doesn’t actually help us relate to the character; he may say he’s in love, but it’s hard to believe him if he never acts on those emotions. However, when Snow finds Serah in the crystal, he commits himself to breaking her out despite opposition from everyone else in the group, and they quickly leave him behind.
Removing Snow from the party like this proves to us that his love for Serah is stronger than his ties to these people that he just met. His actions give substance to his words, and his self-given title of “hero” seems less arrogant and more apt. Unlike the other party members, Snow remains selfless and optimistic even as the world constantly beats him down. He swore to protect Serah so he’ll never abandon her, and he’d rather die than compromise that promise. This absolute devotion to what he believes in establishes him as the most heroic member of the main cast and more effectively demonstrates his love for Serah than any amount of exposition.
Later in this same level, after fleeing from soldiers, Lightning decides to stop running and go on the offensive. She decides to destroy the fal’Cie, but the only fal’Cie that she knows about is the one that maintains Cocoon. Sazh and Vanille object to this idea as it could result in the destruction of Cocoon itself, but Lightning is so resolute in her decision that she abandons the others for her new quest. Hope quickly decides to go with her, dividing the remaining four members into two couples, and these new relationships go a long way in defining each character.
Lightning, as a soldier, directs her anger towards something that she can fight, and the most obvious enemy is a fal’Cie. She doesn’t care if this fight leads to more disaster because she simply needs an outlet for her anger. Everything else is secondary.
Hope, despite his name, has a far more encompassing anger. He wants to destroy the fal’Cie for the same reasons as Lightning, but he also wants to destroy the government and kill Snow because he blames both for the situation that he’s in right now. Hope is angry at the world, and that’s why he decides to travel with Lightning in the first place. He feels a connection with her anger. Whereas Vanille and Sazh would try to calm him down, Lightning’s hate reaffirms his own.
Both couples are at their lowest points in the story so far, and in this depression, we see their uniqueness. They may all be in the same situation, but they react to it in different ways. It’s also important to note that these new couplings (Lightning and Hope; Sazh and Vanille) differ from the couplings established at the beginning of the game. Lightning and Sazh start off fighting together, then Vanille and Hope meet and start traveling together. Since that’s how we’re first introduced to these characters, we naturally associate one with the other, and we identify the individual as part of the couple. So, when those previously established couples break apart, we’re forced to revise our perceptions of the characters.
It’s disappointing that more games don’t play with party unity like this. Usually the growth of your party directly correlates with your progress in the story, but adding characters in this predictable way treats them like new equipment, just something else to collect on your way to the final boss. Breaking up the party along these personal lines helps us identify the characters as individuals rather than as just parts of a whole.