Ten years had passed since Ventus passed the power of the Keyblade on to Sora, and in that time, Darkness had begun to move; slowly at first, but ever growing in power and numbers. One fateful night, Destiny Islands was ravaged and consumed by the Darkness and the Heartless, sending Sora and Riku each on their respective journeys to save their childhood friend Kairi- the same Kairi Aqua had met in Radiant Garden before the battle with Xehanort and Vanitas. The boys had clashed several times since they were separated, and Riku was falling closer and closer to Darkness itself as he believed Sora had replaced him.
Now, Sora, accompanied by Donald and Goofy under their orders to "follow the Key," set foot in the remnants of Radiant Garden- Hollow Bastion. As Ventus had promised him, he had gained his own Keyblade- the Kingdom Key- just as the darkness overtook his home, and he had been using it ever since to fight off the Heartless and seal the Keyholes of the worlds. He was growing stronger and more skilled, but so were his enemies.
The young Keyblade wielder gazed around the Rising Falls of Hollow Bastion, awestruck momentarily by the upward-flowing water surrounding the rocky islets he and his allies tread upon. He snapped out of it and summoned his Keyblade, then ran forward and jumped from rock to rock until he reached a landing that looked like it used to be part of a pathway leading to the castle ahead.
"Riku!" Sora gasped as he found his friend waiting on the other side of the landing. "What are… is Kairi here?"
"If you were so worried about her, you shouldn't have left her in the first place," Riku replied flatly, then pointed at the Kingdom Key. "It's time we stop pretending. The Keyblade wasn't meant to be in your hands, Sora. It chose me."
"Wait, what?" Sora stared at him, confusion evident on his face. "What are you talking about?" As Riku held out his hand, Sora felt his Keyblade try to tug away from him, and it momentarily slipped out of his hands and into his friend's possession. "If you knew what was good for you, you'd leave now."
"As if!" Sora shook his head and summoned his Keyblade back, and it promptly returned to him. "What do you mean 'the Keyblade didn't choose me?' I have every right you do to wield it! Don't tell me you forgot when…" he suddenly found himself lost for the names of the Keyblade wielders who had visited them so long ago. "When that one spiky-blond-haired guy gave me his. Remember that? It was the same thing that other brown-haired guy did when he gave you the Keyblade." Donald and Goofy exchanged an agonized look, obviously dumbfounded by what was occurring before them.
"How a weakling like you could ever actually use the Keyblade is beyond me," Riku chided. "I got mine first. So that, the Kingdom Key, should be mine." Again, Sora felt the Keyblade try to pull away from him, but this time he didn't let it succeed.
"Look, I don't know why it came to me and not you," he insisted, though Riku didn't seem to care. "But I've been using it ever since to fight off the Heartless and save my friends. Even you! I don't want to fight you, Riku!"
"Then hand over the Keyblade and get out of here," Riku told him curtly. "Even with it, you'll never survive in Hollow Bastion."
"I will when I've got my friends," Sora insisted. "No. I won't stop fighting until I know everyone is safe! I won't stop until you, me, and Kairi can go back to the Islands and just be friends again." Despite the passionate response he received, Riku merely shook his head.
"Fine. Don't say I didn't warn you." And, with that, he hurried toward the castle and out of sight, leaving Sora confused and hurt.
"Riku…" he mumbled.
"So Riku can use the Keyblade too?" Donald pondered. "Do you think it really was him that was supposed to get it?"
"I don't know," Sora replied. "And I don't care. I've got it now, and I'm gonna use it to beat the Heartless and save Kairi."
"We're with ya, Sora," Goofy told him in an attempt to lift his spirits, and Sora smiled.
"Thanks, guys. Come on. Let's get going." The trio continued up the rocks until they came to a lift and promptly boarded it. It took them to what seemed like the outer wall of the castle, and the main entrance stood a short distance to their left. Before they could head toward it, though, several large Heartless appeared in their path. Goofy readied his shield, Donald his staff, and Sora rushed forward with his Keyblade at the ready to strike.
Before he could, though, a large, fearsome animal of sorts dropped from nowhere and slashed through the Heartless, making killing them look almost effortless. The trio stared at the newcomer in shock as it turned toward them. It had on torn blue pants and a purple cape, and it had the face of a monster. Despite that, however, its blue eyes looked human.
"Uh, thanks," Sora greeted, scratching the back of his head with his free hand. "Wow. I wish I had your strength when I'm dealing with them."
"Hey!" Donald protested, and Sora looked at him briefly.
"I meant the Heartless," he laughed and turned his attention back to the newcomer.
"You're fighting the Heartless?" he inquired in a deep, rough voice.
"Uh huh. With this," Sora held his Keyblade forward. "I'm looking for someone. What are you doing here? How'd you get here?"
"I'm looking for someone as well… she was kidnapped by these Heartless some time ago." He growled and scratched the ground. "I WILL have her back." He paused. "Are you fighting that arrogant boy?" It didn't take long for Sora to process that he meant Riku.
"I guess," he agreed hesitantly. "If that's what it takes. Well, we could really use some help from someone like you. I'm Sora, and this is Donald," he gestured to Donald, "and Goofy. So, what do you say?"
"Hrm…" their new ally nodded slowly. "Very well. People simply refer to me as 'the Beast.'" The determination that had burned in his eyes when he'd mentioned his missing person quickly returned. "I do not care what it takes: I WILL save her."
"And we'll help you, Beast. Let's go." The small group continued forward, but were again impeded by another swath of Heartless determined to drag them into Darkness. A combination of strikes by the Keyblade, shield bashing, magic, and claws finished off the foes quickly, clearing the path forward. Sora briefly glanced up at the castle, unable to resist wondering how something so beautiful could act as such a home to the Heartless.
Once they reached the main entrance, they found themselves in a great hall with two stories, and a chandelier hung in the center of the ceiling. A small fountain was nestled in the base of the two staircases leading to another hall. The Beast stopped and glanced around, and Sora watched him curiously. Then, suddenly, the Beast growled and lumbered quickly toward one of the room's exits, and he didn't seem to care that he'd left a bewildered Sora, Goofy, and Donald behind.
"Uh…" Donald blinked.
"Do ya think we should go after him?" Goofy wondered.
"We said we'd help him," Sora pointed out as he scratched his head. "Maybe he caught his person's scent or something." He shrugged. "Come on, guys. Let's go."
Before they could go anywhere, though, the door slammed shut.
"You really should quit now," Riku's voice sounded, and Sora turned around to find him standing next to the fountain, holding the bat-winged blade he'd brandished several times since they left Destiny Islands. "You don't have what it takes to save Kairi. You're too weak- Your heart is too weak, and that Keyblade will get you nowhere." Sora blinked.
"Riku…" he mumbled. "No." He summoned his Keyblade. "That guy… he gave this to me because he knew I could wield it. But… even so, my heart has grown stronger since we left. I've met so many people, and they've become a part of it." He stepped forward, new determination burning within him. "It's not the Keyblade that's gotten me this far! My friends are my power!" Riku stared at him.
"Fine. Don't listen to me. Then I'll just have to stop you here before the darkness gets you." With that, a strange light enveloped him, leaving him in a purple, white, and black outfit with what looked like the symbol of the Heartless on his chest. He set his battle stance and Sora, with a pang of regret, readied his Keyblade. Without any noticeable hesitation, Riku shot forth a blast of dark aura, but Goofy blocked it with his shield.
"You've still got us, Sora," he grinned.
"All for one and one for all!" Donald agreed. Sora nodded.
"Thanks, guys," he said softly, then turned his gaze back to Riku. "I'm going to find Kairi! I'm going to save her!"
"Go ahead and try," Riku chided, and both boys rushed forward with the sound of metal on metal resonating around the hall as their weapons clashed. Riku shoved him back and knocked him off balance, but Donald's magic kept him from striking. While he was distracted, Sora attacked quickly with his Keyblade and managed to hit his opponent several times before Riku leapt back and shot forth several blasts of dark magic. Sora dodged around as Goofy bashed Riku with his shield, and Sora sprinted forward to strike once again. Riku grunted and countered, hitting Sora hard in the arm, and the Kingdom Key's wielder retreated briefly. He recovered himself and struck again, and panic crept into Riku's eyes.
He resorted to his dark magic once again and caught Sora off guard, sending him skidding back as his breath was knocked from his body.
"Sora!" Donald called out and cast a spell of Cure, effectively healing him.
"Thanks," he replied quickly and hurried toward Riku again.
"Even with their help, you'll never be able to save her," Riku again told him.
"I'm not going to give up!" Sora yelled and struck again, hitting his friend hard in the side and knocking him back. Riku fell, stunned, and lay there for several moments before he got up slowly with a grunt of effort. His clothing faded back to his usual outfit, and he gripped his side with his eye screwed up in pain. Sora gazed at him steadily until he ran off once again and disappeared to some other place in the castle.
"Riku…" Sora looked down, guilt crashing over him. "Why are you being like this? What happened?" He sighed slowly, then looked back up in the direction Riku had vanished. "C'mon, guys. Let's go." As they started walking forward, the Beast came in and looked around.
"You won that fight because of the strength of your heart…" he noticed, and Sora shrugged gently.
"I just want to find Kairi." He looked over to the Beast. "Hopefully, wherever she is, Belle will be there too." The Beast nodded, and the four of them headed toward the corridor.