"Knights of Heart? What are those?" Sora was intrigued.
"The Knights of Heart are a sacred order of guardians who protect the Princesses of Heart. There is one Knight for each Princess." Yen Sid explained.
"And you know we are Knights because…?" Riku asked, unimpressed.
"It is quite simple; you showed the power of the Knights. Each of the Knights has a different type of heart," Yen Sid continued, "The seven of them represent the seven types of hearts."
"What are the seven types of heart, Master Yen Sid?" Both Sora and Riku were now interested in their new power.
"The three realms ―Light, Dark, and Nothingness― each have type of heart for themselves. Hearts that are completely filled with one of the three, and still capable of being whole," he started to go into more detail about the hearts, "Then there are hearts that are combinations of the three. Hearts like Riku's, which are a combination of Light and Darkness, hearts of Light and Nothingness, hearts of Dark and Nothingness, and hearts like yours, Sora, filled with all three."
"You've identified which type of heart we have?" Riku was appalled. He believed that he should be a complete mystery to everyone and everything, that way he could always do whatever he wanted to do.
"Like I said, these are the seven types of heart. All people have one of the seven. I have a heart of Light and Nothingness. It determines what our true powers will be." Yen Sid was now defending himself from the onslaught of Riku's words.
"You said that there is one Knight for each Princess… What did you mean?" Riku asked.
"Each Knight has a designated Princess. They are sworn to protect them until Kingdom Hearts is finally opened."
"So, what else do the Knights do?" Sora needed to know everything his new title gave him to do.
"When all of the Knights are gathered in one place, the Keyblade of Heart appears."
"The one I controlled when I was possessed by Xehanort's Heartless?"
"It would be the very same, except it would be completed enabling it to open the door to Kingdom Hearts on its own."'
"One last question, Master," Sora almost understood. "What happens when all of the Knights and Princesses are gathered together?"
"Very good, Sora, you're paying attention. When all of the Knights and Princesses are gathered, a special doorway is opened to the heart of all worlds, but not exactly Kingdom Hearts. It is the area outside of Kingdom Hearts. From the information I've gathered, the Guardian of Hearts will appear, bearing the Crowns of Heart. He will call forth one Knight and one Princess to become the King and Queen of Heart."
"So you're saying we have to prepare ourselves to rule Kingdom Hearts?" Riku was ambitious with his chance to achieve power like that.
"Not to rule, but to protect."
"How will we protect it with Keyblades as weak as the ones we have now?" Riku was upset at the lost chance at ultimate power, but he wasn't going to give up now, "We need greater power than what we have now!"
"Calm down, Riku. I know how you thirst for power and hunger for freedom, but we first need to work on finding everyone else first." Yen Sid was getting impatient with Riku's arrogance.
Sora interjected, "What are we supposed to do right now?"
"We ask our friend Mickey to lend us the Kingdom Key – Darkside. We then use the Kingdom Keys from the Light and Darkness to open the doorway for a secret Keyblade. One made from the same crystal as the Door to Darkness. The Crystal Key is one not of this World."
"Not of this world? What do you mean?"
"Legend has it that whosoever opens the true Kingdom Hearts shall have the power to reshape the world however they see fit. They become something greater than human, Heartless, or Nobody could ever be."
"So, what you're saying is that the world has been reshaped before?"
"Yes, and not just once either. The Princesses of Heart are the evidence of this. For each time the world has been reshaped, there was another Princess added to the group. A Keyblade War always ends one Era and opens another. The Χ-Blade is one of the three Keyblades that are instrumental in the War. The other two we've already discussed: the Keyblade of Heart, and the Crystal Key."
"So, you're saying everything we know and love was warped a long time ago by someone we've never met and we're fighting to take that right?" Riku asked, perplexed.
"Not to take that right, but to protect anyone else from taking it." Yen Sid finally gave Sora and Riku their true purpose.
"Well, seeing how you seem to know everything, who are the other Knights?"
"There are four that I know for sure: You two, Sora and Riku, and the other two young warriors I once met, Terra and Ventus…"
