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After the first introductory cutscene, we have two demonstrations of champions knowing each other from their service with Cosmos. Lightning greets the Warrior of Light with a smile, while Cecil, Firion, and Zidane are happy to see one another. Meanwhile, unfamiliar champions are greeted with open arms; the Warrior's first words to a confused Noctis are a sincere "Welcome to the fight", and although Squall is as talkative in his head as ever, he doesn't make any effort to tell Y'shtola to go away.
Tidus and Jecht have their memories back, and they have no interest in fighting each other. Tidus even tells Firion openly that he won't fight Jecht, not this time. And then Jecht pulls a Big Damn Heroes moment to save them from Exdeath, Kefka, and Ultimecia, and evens the odds for a proper 3-3 brawl.
As noted on the main page, Cloud has to this point been in a very unpleasant mood, nomatterwhereheis. In fact, the one time he might have had reason to be joyful for an extended period, he wasn't the focus and we didn't get to see it. Not this time. This time, he's smiling through the fights. He talks amicably with Bartz about memories and conflict. The closest we get to his old depression is him contemplating Sephiroth's taunt. Cloud has earned his happy ending, and it shows.
During Kain's DLC cutscene, Cloud admits that while he was conflicted of the prospect of an alliance with his old nemesis, he no longer lets anything related to Sephiroth hold him down. This gains him Kain's sympathy, as he too is currently atoning for his past crimes. Even Noctis shows his maturity here despite being new to the war.
Noctis: I'd just show them you care. They're gonna see through the act and know you're still conflicted. Don't make them dance around it.
Squall: No use trying to change the past. Just gotta live with it.
While the ending of Final Fantasy IX implied Death Equals Redemption for Kuja, and Dissidia 012 even toyed with the idea of him pulling a Heel–Face Turn, this game goes all the way with it — Kuja switches sides and joins with Zidane and Terra, cementing his reformation by intervening to save them from the Emperor and Sephiroth. While he and Zidane still don't get along and their interactions are Teeth-Clenched Teamwork, it is clear they are not enemies anymore.
Terra remembers Kuja breaking Kefka's control over her in the 12th cycle of war, and thanks him for helping to free her. While Zidane grumbles about it, Terra is happy to have Kuja along with them.
Despite Lightning's pessimistic assumption that Materia and Spiritus are Jerkass Gods, it's clear in very short order that they're nothing of the sort. They're fighting because so many people care about this world. Yes, they called the champions without their consent, and yes, the world requires the power of battle so they're going to make the champions fight each other. But just about everyone is glad to see their friends again, and that is what the gods want to hold on to.
The end of the cutscene before the Final Boss. When Shinryu sends a wave of destruction down against the heroes and villains alike, suddenly alignment doesn't matter, and the two groups work together to defend each other. Garland and the Warrior of Light shield Zidane, Kefka, and Shantotto, Y'shtola protects Cloud, Sephiroth, Firion, and Vaan, Golbez and Exdeath defend Lightning and Noctis, and so forth. It gives a Hope Spot that maybe, just maybe, these long-time archenemies could one day find peace with each other, if they could be so united as one, even if just for a moment. And in the midst of this, one such group? Jecht defending Tidus, alone. When the destruction abates, Tidus slings Jecht's arm over his shoulder and helps him stand.
Warrior of Light: We may have our differences, but in this world, we are one!
The first two DLC cutscenes add Ace and Ramza post-Final Boss, interacting with their fellow champions (worth noting is that Vaan is present in both of these).
Ace admits that he's not used to fighting without his other classmates. Firion assumes that he's referring to friends, but after a moment Ace corrects that they're more like an unorthodox family. The others share that they're from similar backgrounds - Zidane's from a traveling troupe, Firion was orphaned and found by Maria's family, and Vaan's a street urchin - so they know what he means by fighting alongside family.
After a fight on the Floating Continent, Ramza gets into a conversation with Noctis and Cecil about how people of status have a responsibility to those in need. Vaan points out that they're the sort of people that soldiers tend to follow, while Noctis admits that Vaan's cheerfulness helps get him going. Ramza observes that Noctis seems to have had a friend like Vaan in the past.
Terra, Lightning and Y'shtola have a conversation on how World B would unfold under either Spiritus or Materia, while agreeing on the possibility of seeing the regenesis with their own eyes. This just goes to show how much they've grown to care about this world despite what has happened to them in the past cycles of war that dragged them there in the first place.
During the last conflict, a big sticking point for the Warrior of Light was that he doesn't have ANY memory whatsoever of where he comes from, what his quest was or even his own name when everyone else had at least a vague memory of who they were and where they came from because he was born of the conflict between Chaos and Cosmos as a manikin. This time around however when Warrior of Light, Noctis and Cecil end up in Cornelia, he and Cecil are able to share a moment over him now having true memories and a quest to call his own with Warrior of Light happily sharing memories of his quest to save the princess of the castle.
The new cutscene involving three of the DLC characters - Locke, Rinoa and Yuna. All three of them decide to rest under Rinoa's suggestion, with her being new to the war and the other two being veterans (though in Locke's case it was during the events of Secretum). It's a very touching scene, which implies that Locke and Yuna have found Rinoa who has been lost upon being summoned for the first time and all three consequently befriending each other despite being from different worlds.
Lightning: I'm glad you were around. You helped me keep my cool. Couldn't have done it without you.
A post-Shinryu cutscene has Kam'lanaut doing something to the energy born of battle. Golbez catches him and reprimands him, and after a bit of conversation, Kam'lanaut expresses the sentiment that a ruler is duty-bound to compensate his servants for their efforts. Golbez suggests that he take it up with Spiritus. The description for the cutscene panel afterwards proclaims that Kam'lanaut did - and Spiritus obliged. It's a far cry from the last conflict, where Chaos's faction suffered from a plague of Chronic Backstabbing Disorder and the idea of cooperation was basically forced by the assist system in 012 Prologus.
