Arguably, Birth By Sleep is one of these for the entire series. Gameplay-wise It has been widely praised as having the best combat system so far in the series. Story-wise, not only does the game probably provide more answers than questions about the Kudzu Plot that Kingdom Hearts has become, but it also makes a rather strong effort to connect the Disney worlds to the main plotline, as opposed to COM, Days, Coded, and a good half of KH2, wherein the Disney worlds seemed tacked on.
All three final bosses.
When Master Xehanort commits Grand Theft Me on Terra and emerges as the young Xehanort, he begins to walk away when Terra's armor reforms and conjures a barrier of light around the arena. First, Theme Music Power-Up because the battle theme is Raged Awakened, the theme when fighting the Lingering Sentiment. Second, Terra uses the Power of Hate to become Animated Armor and battle Xehanort in his own body. Third, you get to take control That One Boss to deal a beatdown on the main antagonist of the series who up until now has been The Unfought. And fourth, for once the barrier around the arena isn't the boss's, it's Terra's -- he's making sure Xehanort has nowhere to run.
Also a subtle bit of foreshadowing - the barrier is made up of chains of light, Eraqus's attack.
Ventus uses Heroic Willpower to unfreeze himself to protect Aqua from Vanitas. Then Vanitas unmasks himself and merges with Ventus, leading to a Battle in the Center of the Mind on a corrupted Dive to the Heart showing Vanitas opposite Ventus. Ventus fights knowing full well that if he destroys the X-Blade, both of them will lose their hearts. But as he says, "anything to save Terra and Aqua.
As Aqua and Mickey encounter a spacey Ven, the former approaches him to ask what is going on. Mickey instantly realizes there's something fishy about the situation, so when "Ven" reveals himself to be Vanitas possessing the poor kid and immediately tries to stab Aqua with the χ-Blade, the King jumps in, blocking in with his Star Seeker when the χ-Blade was millimeters from Aqua's heart! It's right there you know King Mickey took one of his many levels inBadass.
Also a crowning moment for Vanitas, in which he shows that he is Chaotic Evil not Chaotic Stupid. This is the second time that he's attacked Aqua without warning, because he's faced her twice in the past and she won. He's the only villain smart enough to use sneak attacks.
Seeing Cinderella's wicked stepfamily get what's coming to them!
Scrooge McDuck talked back to an Unversed. Sure, he's badass in his canon, but that still takes balls to do that while unarmed.
He probably would've won, too. All because he thought the Unversed may have been after his munny, of course. That's right, when faced with possible death, Scrooge only cares for the safety of his well-earned munny. Now that is Badass.
AnotherCool Old Guy from Disney has a great moment in Ven's story...
Ven: "Mister, get inside! It's not safe out here!" Merlin: "Oh, ordering me about--now that's unsafe!"
Needless to say, Ven doesn't push the issue any further after that.
Aqua creates Castle Oblivion. This place was the whole mysterious setting of KH:CoM and it's almost a mindfuck when you learn that it was Aqua who created it. She modified a whole world!
Another thing about Aqua: Gameplay-wise, she canonically beats both of the other main character's final bosses. Hell, she took on Ventus's twice! And she beat the Memetic Badass, Vanitas, three times, with the last one being when he is in possession of the ultimate weapon!
Vanitas has some impressive Crowning Dialogue of Awesome, though some of it may also count as Nightmare Fuel. Among the greatest examples for him is this: "In that case, I'll choke the life out of your friends. Then let's see how long you play the pacifist."
I thought the scene where Terra is watching his home world being destroyed was pretty freakin' sweet. Not because the world itself was being destroyed (that's sad), but with the way the camera shook while he was just watching made the scene look intense.
After Ventus is frozen solid by Xehanort, he is dropped down to where Aqua is, who then has to fight Braig, and all he can do is watch. Then Aqua gets hit by Vanitas' sneak attack, and Ventus DEFROSTS HIMSELF WITH HIS ANGER to fight him.
"You may be my master but, I will not let you hurt my friend! was a pretty epic one for Terra, even if it turned out prettybadlyforhim.
"My name is Master Aqua. Now return my friends heart or pay the price" Aqua proving she is by far the biggest badass amongst the main characters.
A villainous example has to be when Braig, pissed that he got scarred from a fight that Xehanort set up, starts shooting at him. How does Xehanort take this? He just sits back and lets the bullets hit his shield. And then, when Braig gets in close range, Xehanort just summons his Keyblade right to his throat, causing Braig to back down his aggressiveness.
