KINGDOM HEARTS 3.6 Part I.5: Prologus -Sora-.
Sora enters his Dive to the Heart in his Kingdom Hearts III outfit. He lands on his Station of Awakening, surrounded by four mirrors. Each containing a past version of himself: the north mirror represents his 4 year old self from Kingdom Hearts Birth by Sleep. the south mirror represents his 15 year old self from Kingdom Hearts II. Both the west and the east mirrors represent his 14 year old self respectively, the west in turn representing his original Kingdom Hearts self and the east his Kingdom Hearts 3D: Dream Drop Distance self. Suddenly, the four copy Soras surrounding the original KH III Sora in the middle disappear. All transforming into a singular Light that shines very brightly and engulfs Sora as a whole. After the Light disappears, he finds himself on the beach of the Destiny Islands, surrounded by three of his past allies-Cloud, Leon and Auron.
Here, each of the three gives Sora a different question that he must answer, upon the chosen choices of his answers, he will both gain something and lose something. By talking to Cloud, he will say does Sora ask for Strength. By talking to Leon, he will say does Sora ask for Wisdom and by talking to Auron, he will say does Sora ask for Balance. By choosing two of three answers, leaving out the 3rd, Sora's path will have already been set into motion.
Suddenly, the Destiny Islands revert to the state they once were in when they were consumed by Darkness. Sora summons his Kingdom Key Keyblade in response, wondering what is going on. Pureblood Shadow Heartless then appear and start attacking Sora, only for him to swiftly defeat them. Afterwards, Sora makes his way to the secret spot, believing on a hunch that he will find some answers there.
By opening the door inside of the cave that is the secret spot, a wave of Darkness gushes forth, swallowing Sora whole. At first, he believes himself to have been lost to Darkness, only for a floating Heart to appear and reassure him otherwise. It starts to guide him towards other floating Hearts of pure Light, all of them together seven in total.
Four of the Hearts take on the visual images of Rapunzel, Elsa, Anna and...Kairi. Upon seeing the latter, Sora is greatly shocked. Before he can say anything however, the Heart that guided him here speaks it's piece. It reveals that although Sora's Destiny has been fulfilled, there is still so much more left for him to do. By averting the 2nd Keyblade War, only far more dangerous threats have been "awakened" as a result. Sora must regain his "complete" form if he is to battle this "new Darkness" as the floating Hearts call it.
To test him, they then transform the whole area into a new Station of Awakening, based on the cover box art of Kingdom Hearts III. Afterwards, a Twilight Thorn appears, attempting to attack Sora. He dodges before the floating Hearts inform him that fighting the Twilight Thorn is part of the test they have given him. To start things off, Sora is forcibly taken away the ability to use the Keyblade, instead, he must rely on the given magics gifted to him at the test's start. The available three magic spells are Fire, Blizzard and Thunder. Sora must think outside of the box and learn how to combine these spells all into one, using them to his advantage.
Sora quickly learns in the heat of battle the "Thaumaturgy" gameplay system. It allows him to combine up to two-three spells each, provided the respective magics can mesh well together more or less. Upon breaking the Twilight Thorn's defence, otherwise known as the "Opening Break" gameplay mechanic. Sora can now quickly harm the Twilight Thorn's central weak points before it fully regains both it's defence and composure.
Recognizing his latent skill returning to him slowly, Sora is bequeathed use of the Keyblade once more, however, it takes on a new shape. It is now "Dawn Till Dusk" rather then the "Kingdom Key" Keyblade. The floating Hearts reveal that through Sora's multiple battles up to now and them having added a little of their own combined magic to his Keyblade, it has evolved to become what it is now. Utilising this "new" Keyblade right off the bat, Sora immediately regains use of his Ragnarok ability as a Shotlock, using it to finish off the Twilight Thorn.
Afterwards, the floating Hearts reveal to Sora the truth behind the losses of his previous growth experiences. They reveal that it wasn't because of outside circumstances. Rather, the reason why Sora kept losing his powers again and again was because his Body could not handle all of them...not as he currently was at the time that is. The Seven Pure Lights of the Worlds that the Seven Princesses of Heart safeguard had acknowledged Sora's existence as an important one and thus had resolved to make sure that too much of his great power would not corrupt who he truly is in his Heart on the inside.
They also reveal that a far more dangerous "new Darkness" is soon to approach and threaten the Worlds. Unfortunately however, Sora is trapped in "Limbo" and cannot escape without outside help to combat this "new Darkness". For the time being, the floating Hearts, or rather, their Seven Pure Lights have now also resolved to take away Sora's Memory of talking with them, believing that it may affect his judgement later on within the future. They do assure him however that he WILL be saved. As Sora remains trapped inside of "Limbo" itself, there are those on the other side that are and/or will attempt to rescue him. Furthermore, before sending him into a deep sleep, they also assure Sora that Kairi as a Princess of Heart's time has ended, her powers have passed on to another. Who this "other" is Sora fails to hear, having completely fallen asleep at that point.