Sonic Adventure x Kingdom Hearts: The Power of Chaos
Disclaimer: This story is a creative endeavor and is not intended to infringe upon the intellectual property rights of Sega, Sonic Team, Disney, Square Enix, or any other affiliated parties.
The Sonic the Hedgehog franchise, including its characters, settings, and related elements, is the intellectual property of Sega and Sonic Team. Kingdom Hearts, including its characters and associated content, is the intellectual property of Disney and Square Enix.
"Sonic Adventure x Kingdom Hearts: Chronicles of Chaos" takes place after the events of Sonic Forces and Kingdom Hearts III ReMIND. This fan fiction takes place in the year 2018, due to the merging of these timelines, following the Sonic games chronicle of events as a primary source. The story exists within a shared universe that combines elements from both franchises, and it may also include appearances from characters of other franchises.
I wonder what other cosmic and critical event occured in 2018?
Present Day - Early 2018: Eggman's Base - Location: Unknown.
In the hidden recesses of a secret base located in an unknown, far-off location, Dr. Eggman sat in a dimly lit room. The walls were adorned with screens displaying data, schematics, and blueprints of various contraptions. In the center of the room, Eggman's eyes were fixated on a large monitor, showing footage captured by one of his hidden badniks. This particular recording had been replayed many times, and it chronicled the dramatic events of the Keyblade Graveyard.
As Eggman watched, the story played out before him: the clash of keyblades, the emergence of familiar heroes, the darkness, and the triumphant & defeat of Master Xehanort. He couldn't help but feel a mixture of awe and frustration, for it was a story filled with power, mystery, and the potential for world-altering technology.
"Doctor Eggman, sir!" came a high-pitched, robotic voice from behind him.
Startled, Eggman swiveled in his chair to see Orbot and Cubot standing there, their mechanical bodies adorned with their usual bickering manner. Orbot's eye's glowed with a sense of irritation, while Cubot's square yellow head bobbed comically.
"Can't you see I'm busy?" Eggman snapped, his mustache twitching with annoyance. "What do you want?"
Orbot responded, his voice tinged with sarcasm. "Are you still watching that tape again, Doctor? It's like the 200th time."
Cubot chimed in, always eager to correct. "Actually, Orbot, it's the 201st time!"
Eggman clenched his fists, his frustration boiling over. "Yes, yes, I'm watching it again, and I'll watch it as many times as I like!" He couldn't help but feel a deep fascination with the events he had observed, especially the powers wielded by the keyblade wielders.
Orbot and Cubot exchanged a knowing glance before Orbot spoke again. "Perhaps, Doctor, it's time we focus on your own plans and inventions. You know, instead of obsessing over these... Keyblades and the Heartless?"
Eggman shot them a menacing glare. "My plans are always in motion, you rusted scrap heaps! Don't you dare question my genius!"
Orbot and Cubot, used to their master's outbursts, simply nodded and continued with their usual banter. "Of course, Doctor, we would never doubt your genius," Orbot said, his tone dripping with false sincerity.
"Righto, never a doubt, boss," Cubot added with an exaggerated nod.
Eggman sighed deeply, knowing he was surrounded by mechanical idiots. Rubbing his temples, he tried to concentrate.
"Is there a problem, boss?" Orbot exclaimed, looking to his master with concern.
"Do you need your headache pills?" Cubot chimed in with a sense of urgency. "You do become cranky when you've got a headache coming on."
"No, thank you. It's not a headache. It's overthinking my genius brain into overdrive." Eggman proclaimed, still rubbing his temple, watching the monitors closely.
"Oh, what's on your mind?" Orbot asked,seeking answers from Eggman.
"You sure it's not a migraine?" Cubot quipped, pulling out a pack of headache tablets and a glass of water. "We know how much overthinking rocks your flow, Doc."
Eggman again sighed deeply and leaned back in his chair. His frustration with Orbot and Cubot's lack of understanding was becoming more pronounced. He had to get through to them.
"No, No, NO! You simpletons!" Eggman snapped, his patience wearing thin. "It's not about what's happening on the surface. It's what's beneath it all that bothers me."
Orbot and Cubot exchanged puzzled glances once more. "Beneath it all, sir?" Orbot inquired.
Eggman leaned forward and gestured at the monitor, which displayed the chaotic Keyblade Graveyard battle. "Look closer," he insisted. "There are inconsistencies in this scene, like a movie with a glaring plot hole."
As the robots launched into their outlandish theories, Orbot and Cubot couldn't help but amuse themselves with their own absurd ideas.
Orbot quipped, "Perhaps the popcorn-themed Heartless were the key to the whole thing. They popped in and out of existence, causing the timeline to unravel!"
Cubot chimed in, his voice filled with mock seriousness. "And those interdimensional snacks? Clearly, they were the catalyst for the entire battle. A snack attack of cosmic proportions!"
The two robots burst into mechanical laughter, their antics briefly breaking the tension in the room. Even Eggman, in the midst of his scheming, couldn't help but crack a reluctant smile at their absurdity.
However, with the annoying laughter and banter continuing from his two robots, Eggman's patience finally reached its limit, and he slammed his hand down on the control panel. Data appeared on the screen, showing anomalies in the scene correlated with the power of the Phantom Ruby.
"Enough of your foolishness!" Eggman shouted. "This is serious!"
Orbot, finally catching on to Eggman's mood, asked, "Could this be the link to the Chaos Emeralds going missing, Doctor?"
Eggman's mustache twitched as he considered the possibility. "Perhaps," he mused. "But it's that boy." He pointed at Sora on the screen. "Something I picked up in his data scans... Something doesn't sit right."
He glanced at the screen, where Sora had vanished from view, and the Chaos Emeralds had gone into hiding. "It's a rather curious theory," he added, his mind whirring with possibilities.
Orbot leaned in, genuinely intrigued, and asked, "What exactly is this curious theory, Doctor?"
Eggman rubbed his gloved hands together, a devious grin forming on his face. "Well, Orbot, my theory is rooted in something I stumbled upon in a piece of research from my grandfather's archives. It evaluated and explored the works of a certain Professor Pickle and an individual known as 'Ansem the Wise.'"
He continued, "According to this research, Professor Pickle and Ansem delved into the connection between hearts and chaotic energy, a concept I've only recently come to appreciate fully. You see, my theory revolves around the power of hearts, specifically those of individuals with extraordinary abilities, like our friend Sora."
Eggman leaned closer to the monitor, his eyes gleaming with the excitement of discovery. "The hypothesis suggests that when the hearts of such individuals interact with a powerful energy source like the Phantom Ruby's reality warping properites for example, it could trigger anomalies in the very fabric of reality. In Sora's case, it's his ability to traverse different worlds, this 'power of waking' the research speaks of, and the strength of his heart that might have caused these disruptions."
Orbot processed the information, his optic eye narrowing in thought. "So, you believe that Sora's actions, combined with the Phantom Ruby's influence on our world, could have inadvertently led to the Chaos Emeralds going into hiding?"
Eggman chuckled menacingly. "Precisely, Orbot. And if that's the case, then there's an opportunity for us to harness this power, to bend reality to our will, and to finally achieve the dominance I've longed for over Mobius and beyond."
Cubot, always the inquisitive one, couldn't help but chime in, "But what's this 'power of waking,' boss? Sounds like something you'd need after a long nap!"
Eggman's frustration reached new heights as he rolled his eyes and muttered under his breath, "You imbecile," before turning his attention to Cubot. He spoke in a condescending tone, "The 'power of waking' is a complex and highly sophisticated concept, far beyond your limited comprehension."
Cubot shrugged off the insult with a carefree grin, but Eggman continued with his explanation, ignoring the robot's goofy demeanor.
"According to my grandfather's research, which referenced the findings of Ansem the Wise and Professor Pickle, the power of waking is a unique ability possessed by certain individuals. It allows them to traverse the hearts and minds of others, to unlock the mysteries of the multiverse, and to awaken those who have fallen into slumber."
Eggman's eyes narrowed as he made the connection. "And it's precisely this power that might have caused Sora's disappearance, leading to the Chaos Emeralds vanishing alongside him. If we can understand and control this power, we may hold the key to unlocking unimaginable possibilities."
Orbot nodded in understanding, realizing the potential significance of this theory. "So, Doctor, what's our next step?"
Eggman's grin widened as he gazed at the monitors, pondering the vast potential that lay before him. "Our next step, my dear Orbot, is to find this Sora and harness the power of waking for our own purposes. With the Chaos Emeralds and this newfound power, there will be no limit to what we can achieve."
The hypothesis and theory by Eggman's research and data collation had some weight towards it. If Sora is linked to the missing Chaos Emeralds, perhaps there is some theory in this madness. The reality warping effects of the 'power of waking', the Phantom Ruby and the Emeralds connection might hold strong evidence of Sora's disappearance. However mad or over-analytical, Eggman always thought of scenarios and theories that could baffle the brilliant minds of the past.
However, it was Cubot who dampened this idea. Like an unintentional bearer of bad news, he couldn't help but interject once more to Eggman's theories.
"But Boss, isn't the kid missing from this reality?" Cubot asked, his robotic voice with a sense of disappointment to the Doctor's ideas.
Eggman scowled at Cubot, shaking his head. "You just have to ruin every idea, don't you?" He took a deep breath and adopted a more composed demeanor. "But fear not, Cubot. Eggman always has a plan."
"Plan, what plan?" Orbot inquired, wanting to know what was on his master's mind.
Standing from his chair, Eggman addressed his robotic companions with a determined expression. "Orbot, Cubot, we're going to pay a certain sorceress a visit. She's been seeking a 'black box,' which, in turn, could lead us to more answers."
Orbot, aware of the sorceress in question, let out an exasperated sigh. "Oh no, you're not talking about her, are you?"
Cubot, his optics wide with trepidation, stammered, "You mean... her?"
Eggman grinned wickedly. "Absolutely. My dear Maleficent may hold the further answers we seek. So, brace yourselves, you two, and let's go."
Cubot shuddered, admitting, "That name gives me the creeps. If I could, I'd be wetting my pants right now."
Orbot chuckled, patting Cubot's robotic shoulder reassuringly. "Don't worry, my friend. The Doctor always has a plan."
From a distance, Eggman called out impatiently, "Move it, you two!" The trio prepared to embark on their journey to seek out Maleficent, their path leading them further into the mysterious and interconnected worlds of chaos and power.
Timeline of Events
Timeline of this Story and shared universe, which we shall call Universe 626.
Ancient Times:
Darkness sweeps over the universe, plunging it into chaos.
The Big Bang brings light into existence, and seven Chaos Emeralds are created to balance the darkness.
Ancient Times - Echidna Tribe:
The powerful creature Perfect Chaos wipes out the Echidna Tribe, leading to the Knuckles Clan becoming the last of their kind.
Keyblade War (First Occurrence):
The first Keyblade War occurs, resulting in the scattering of Keyblades across different worlds and the formation of the Keyblade Graveyard.
Late 1940s: The Opening of the ARK
The Space Colony ARK is established as a top-secret research facility for scientific testing, experimentation, and weapons of mass destruction.
1950s: THE ARK INCIDENT
Doctor Gerald Robotnik is brought to the ARK, along with his family, including his granddaughter, Maria Robotnik.
Gerald is tasked by the President of the United Federation with "Project Shadow." Using Black Doom's DNA, Shadow the Hedgehog is created. The Biolizard was also developed during this time.
Concerns grow within the government about Gerald's work and his sanity.
A G.U.N. military operation takes place on Space Colony ARK, resulting in the infamous incident that leads to Maria Robotnik's death, Gerald's arrest, and Shadow the Hedgehog being put into stasis.
A young Ansem the Wise graduates from Spagonia University, specializing in philosophy.
He becomes a lecturer at the university, where he meets his future friend and research partner, Professor Pickle.
1955: Ansem & Pickle
Ansem the Wise and Professor Pickle collaborate on their first research journal together, marking the beginning of their scientific partnership.
1960s: Young Keyblade Masters in the making
A young Xehanort and Eraqus meet during their Keyblade training, setting the stage for their future roles in the Kingdom Hearts universe.
1960/1970s - Gerald's Imprisonment and Execution:
Gerald Robotnik is imprisoned on Prison Island, where he gradually loses his sanity.
Due to charges of treason against Mobius and the United Federation, Gerald is executed by G.U.N.
The discovery of the Eclipse Cannon on the ARK further escalates tensions.
1970s: Ansem's Quest
Ansem the Wise, after writing his fifth and final collaborative journal with Professor Pickle, decides to leave his post at Spagonia University.
He chooses to pursue further research opportunities and relocates to Radiant Garden to continue his scientific endeavors.
Professor Pickle continues to teach at the university, continuing their academic legacy.
1980s: The Rise of Ivo Robotnik
Doctor Ivo Robotnik, the grandson of Doctor Gerald Robotnik, begins his scientific endeavors on Mobius.
He builds his first robot and secretly plots to seek revenge against Mobius and G.U.N., who he believes betrayed his family's legacy.
1980s - Xehanort and Eraqus:
After years of dedicated mentorship under Master Yen Sid, Xehanort and Eraqus both achieve the rank of Keyblade Masters.
This significant milestone in their training sets the stage for their future roles in the Kingdom Hearts saga.
1991 - The Rise of Sonic the Hedgehog:
A young blue hedgehog named Sonic rushes onto the scene to stop the schemes of the evil scientist Dr. Robotnik (later known as Dr. Eggman).
Sonic's adventures begin as he collects Chaos Emeralds to thwart Robotnik's plans to turn animals into robotic minions and seize control of South Island.
1992 - Sonic meets Tails:
Sonic is joined by his trusty sidekick, Tails, as they journey to stop Dr. Robotnik from collecting the Chaos Emeralds to power his new superweapon, the Death Egg.
1993 - Sonic v Metal :
Sonic travels through time using the power of the Time Stones to save Amy Rose from the clutches of Metal Sonic and prevent Robotnik from altering the past.
1994 - Sonic & Knuckles:
Sonic and Tails join forces with Knuckles the Echidna to thwart Robotnik's plans to steal the Master Emerald.
The story unfolds as Sonic and his friends discover the existence of the Death Egg and Chaos Emeralds on Angel Island. Together, they stop Robotnik's ambitions and prevent the doctor taking over not just Mobius, but the universe.
1995 - Xehanort's Proposal:
During Robotnik's brief period of hiding and reflection following the events of Sonic & Knuckles, Xehanort approaches him with a research proposal related to the darkness.
Robotnik, however, rejects Xehanort's offer, considering it too risky and unrelated to his own goals.
1999 - Sonic's Chaotic Adventure:
Sonic's adventures continue as he faces off against Dr. Robotnik, who has now taken on the moniker "Dr. Eggman."
Eggman's release of Chaos from the Master Emerald leads to a series of events that involve Sonic and other characters.
The story unfolds as Sonic, Tails, Knuckles, Amy, and others must collect Chaos Emeralds to prevent Eggman's nefarious plans and put an end to Chaos' destructive rampage.
2000 - Xehanort and Eggman:
Master Xehanort makes another attempt to lure Dr. Eggman to his cause, but Eggman remains focused on diving deeper into his grandfather's research, determined to uncover its secrets.
2000 - The Beginning of Training:
Master Xehanort shifts his attention elsewhere, rekindling his relationship with his old friend Master Eraqus.
Master Eraqus has begun training a pair of young Keyblade wielders, 12-year-old Terra and Aqua, as they embark on their journeys to become Keyblade Masters.
2001 - Sonic & Shadow:
The events of Sonic Adventure 2 unfold, with Sonic and his allies facing off against Dr. Eggman, Shadow the Hedgehog, and the sinister Biolizard.
Shadow learns about his past and his promise to Maria, to save Mobius and to give Mobians a chance.
2003 - Sonic Heroes:
Sonic and his team, consisting of Sonic, Tails, and Knuckles and other teams such as Team Rose, Team Dark and Team Chaotix unite to thwart Dr. Eggman's latest plot, which involves the mysterious "Metal Sonic" and the creation of the ultimate weapon.
2005 - Black Doom:
The Black Arms, led by Black Doom, arrive on Mobius in search of the Chaos Emeralds they were promised by Gerald Robotnik.
The events of Shadow the Hedgehog transpire as Shadow, with his amnesia, navigates through various paths, making choices that determine the outcome of the story.
Shadow once again learns about his past and that Shadow was created as a beacon of hope by Gerald. He ends Black Doom's schemes and destroys the Black Comet.
2005 - Birth by Sleep:
The story of Birth by Sleep begins, as Terra, Aqua, and Ventus embark on their journeys.
Manipulated by Master Xehanort and the darkness, the trio is separated during their adventures.
During this time, Terra visits the Destiny Islands and bequeaths the power of the Keyblade to a young Riku, setting the stage for Riku's future role as a Keyblade wielder.
Aqua meets Kairi in Radiant Garden, and Kairi becomes connected to her Keyblade when she touches it.
Ventus's heart finds refuge within Sora's heart, setting in motion the events of Sora's journey in the Kingdom Hearts series.
Unfortunately the Wayfinder Trio's fates are sown into this reality. Terra falls to the darkness and becomes Master Xehanort's vessel, becoming Terranort. Aqua falls into the Realm of Darkness, trying to save Terra. Ventus enters a deep slumber after his heart is fractured during his conflict with Vanitias, when trying to create the x-Blade.
2006 - Terranort's Betrayal and Kairi's Arrival:
Terranort, now a member of Ansem the Wise's research division, ultimately betrays his master and takes control of the division.
This act of treachery results in the banishment of Ansem the Wise, who is forced to go into hiding.
Terranort's actions also lead to a young Kairi being sent to the Destiny Islands, as her presence is necessary to find the future Keyblade wielder on that world, setting the stage for her connection to Sora & Riku.
2006 - Sonic's Visit to Solenna and Mephiles the Dark:
Sonic embarks on a journey to Solenna and faces off against Mephiles the Dark, a powerful and malevolent entity.
The timeline during this period is ultimately erased due to the actions of Princess Elias, who extinguishes the flame of Solaris, preventing Mephiles from causing further chaos.
Silver the Hedgehog, a telekinetic hedgehog from a bleak future, is introduced to the timeline during these events.
2007 - Radiant Garden's Fall and Transformation into Hollow Bastion:
As a consequence of Terranort's actions and the growing darkness within Radiant Garden, the once-beautiful world falls into darkness and despair.
The world undergoes a transformation and becomes known as Hollow Bastion, a place of darkness and Heartless.
The fall of Radiant Garden has a profound impact on the Kingdom Hearts universe and its key characters.
During this time - Terranort began experimenting and managed to separate his heart from his body, creating his Heartless and Nobody. The Heartless Terranort took the name 'Ansem' Seeker of Darkness, with his Nobody becoming Xemnas.
2008 - The Werehog:
Sonic's adventures continue as he is exposed to Dark Gaia's influence when Mobius was broken apart by lead to the transformation of the Werehog, a powerful and beastly form.
During this time, Sonic encounters Chip, who is revealed to be Light Gaia, a being with the power to counterbalance Dark Gaia.
With the help of Tails and Professor Pickle, Sonic and Chip learn about the temples where the Chaos Emeralds must be placed to rebuild the broken world.
Sonic and Chip team up to restore the world and defeat Dark Gaia's influence, traveling to various locations across the globe.
2010 - Sonic's Visit to Planet Wisp:
Sonic embarks on an adventure to Planet Wisp, a lush and vibrant world filled with unique challenges.
While on Planet Wisp, Sonic encounters new allies and faces off against Dr. Eggman's latest schemes.
2011 - Sonic Generations:
Sonic faces a new threat, the Time Eater, which is disrupting the fabric of time and space.
He teams up with his younger counterpart, Classic Sonic, who hails from another dimension where the events of Sonic Adventure didn't occur.
Together, they race through time to save Sonic's friends and restore the timeline.
2013 - Sonic and the Deadly Six:
Sonic takes on the Deadly Six, a group of powerful antagonists, in a quest to thwart their destructive plans.
2015 - The Start of Sora's Journey (Kingdom Hearts):
Sora begins his epic journey in the Kingdom Hearts universe after his home is engulfed by darkness, with his friends Riku and Kairi missing.
He teams up with Donald and Goofy to traverse various worlds in search of his friends, seal the keyholes of the worlds they visit, learn about the power of the heart and to combat the Heartless.
2015 - Creation of Roxas and Kingdom Hearts 358/2 Days:
During his journey, Sora must save Kairi, who is trapped within his heart. In a selfless act, Sora sacrifices himself to restore Kairi's heart to her body.
This self-sacrifice leads to the creation of Roxas, Sora's nobody, who is taken by the Organization XIII. Roxas's story unfolds in Kingdom Hearts 358/2 Days as he navigates the complexities of his existence.
Late 2015 - Castle Oblivion and Sora's Memory Manipulation:
Sora stumbles upon Castle Oblivion, where he faces members of the Organization and meets Naminé, who has been manipulating his memories.
Due to the effects of Castle Oblivion, Sora, Donald, and Goofy must go into stasis for a year to recover from the memory manipulation.
During this time, Roxas is taken to the digital Twilight Town by Riku and Ansem the Wise, who is operating under the alias "Diz.
Early 2016 - Eggman's Encounter with Xemnas:
Dr. Eggman, during one of his many hiatuses to scheme new plans, is visited by Xemnas, the leader of Organization XIII.
Xemnas proposes a collaboration, but Eggman declines, firmly stating his ambition to rule the universe through his research on something known as 'The Phantom Ruby.'
Xemnas issues a veiled threat, leaving Eggman wary of the Organization XIII members and adding them to his list of enemies.
During this time, Eggman also stumbled upon a piece of research completed by his grandfather, linking hearts and chaotic energy, connecting him to the work of Ansem the Wise and Professor Pickle.
Late 2016 - Kingdom Hearts II Events:
Sora and his friends take on Organization XIII, with the main antagonist, Xemnas, seeking to exploit the power of Kingdom Hearts.
The events of Kingdom Hearts II occur, leading to the defeat of Xemnas, the Nobody leader, and the temporary resolution of the Organization's threat.
Early 2017 - Sora and Riku's Mark of Mastery Exam:
With the looming threat of Master Xehanort's return, Sora and Riku embark on their Mark of Mastery Exam.
This challenging journey is prompted by the defeats of Ansem and Xemnas, which have the unintended consequence of resurrecting Master Xehanort.
Master Xehanort's manipulative efforts nearly lead to Sora becoming a vessel for the Organization, but he is saved by the combined efforts of Riku, Mickey, Donald, Goofy, and Axel.
Early 2017 - Rise of Infinite:
Eggman hires the Jackal Squad to do his bidding, with most of them being defeated and killed by Shadow the Hedgehog.
One member of the Jackal Squad survives, but is considered weak by Shadow.
Determined to become stronger, this surviving member undergoes experiments with the Phantom Ruby, leading to the creation of Infinite.
Mid-2017 - Sonic's Capture and the Rise of the Resistance:
Dr. Eggman, with the assistance of Infinite and the Phantom Ruby, manages to capture Sonic the Hedgehog, imprisoning him for several months.
This event leads to the formation of the Resistance, an alliance led by Knuckles the Echidna, in response to Eggman and Infinite conquering 99.99% of Mobius.
The Mobius government falls under Eggman's control, driving the need for a unified resistance force to combat his rule.
Mid-2017 - Preparations for the Keyblade War:
Sora, having regained his strength after narrowly avoiding becoming Xehanort's new vessel, joins the Guardians of Light.
The Guardians begin preparations for the impending Keyblade War against Master Xehanort's 13 Darknesses with their own 7 Guardians of Light.
Axel, now going by his real name Lea, and Kairi embark on intensive training in a pocket dimension created by Merlin.
Riku and Mickey set off on a quest to locate the missing trio of Terra, Aqua, and Ventus, crucial allies in the battle against Xehanort.
Mid-2017 - The Rise of 'Rookie' and the Liberation of Sonic:
A hero from a fallen city joins the Resistance and earns the nickname 'Rookie' among the group.
The Resistance obtains critical intel revealing that Sonic is alive but imprisoned on Eggman's space station.
With the help of 'Rookie' and the unexpected return of Classic Sonic, who journeyed through space and time using his own Phantom Ruby, a daring mission is launched to free Sonic from his captivity.
Sonic, Classic Sonic, and 'Rookie,' along with the Resistance's collective efforts, join forces to take down Eggman and Infinite, liberating Mobius from their oppressive rule.
Mid to Late 2017 - The Battle of Light & Darkness:
The long-anticipated Keyblade War begins to unfold as the 13 Darknesses clash with the 7 Guardians of Light.
Sora, Mickey, and Riku embark on a mission to save Aqua from the Realm of Darkness.
Aqua, in turn, helps restore Castle Oblivion to its original form as the Land of Departure, and the group discovers the slumbering Ventus within.
Ventus is awakened by Sora's power of waking, adding his strength to the team.
The group, composed of Sora, Riku, Kairi, Lea, Aqua, Ventus, King Mickey, Donald, and Goofy, faces Master Xehanort's 13 Darknesses at the Keyblade Graveyard.
Terra returns and frees himself from the darkness imposed by Terranort, rejoining the Realm of Light.
Roxas and Xion also make triumphant returns, bolstering the heroes' forces against the darkness.
The battle is intense, but it takes a tragic turn when Kairi is killed by Master Xehanort, leading to the formation of the x-Blade and Kingdom Hearts itself.
In a final showdown, Sora, Donald, and Goofy confront Master Xehanort at Scala ad Caelum, where they succeed in defeating him and ending his malevolent plans.
Sora's Quest to Save Kairi:
Sora, driven by his unwavering determination and love for Kairi, embarks on a solo quest to find a way to bring her back to life after her tragic death at the hands of Master Xehanort.
Utilizing the power of waking and time travel, Sora journeys back in time to influence critical events in the past. His actions lead to Terra's return to the Realm of Light, Roxas and Xion becoming real people rather than Nobodies, and the recovery of the shattered crystals of Kairi's being, which were smashed during the battle at the Keyblade Graveyard.
However, this extensive use of the power of waking and time travel takes a heavy toll on Sora, and he ultimately vanishes as a result of his self-sacrificing efforts.
The Search for Sora:
Kairi, Riku, and the remaining Guardians of Light embark on a heartfelt quest to find and rescue Sora, determined to reunite with their dear friend and savior.
There is a belief that Sora could be found by looking through Kairi's memories, this is just a hypothesis at the moment by Ansem the Wise, who has seeked council with his research team and words of advice from his past research partner, Professor Pickle.
Returning to Normal Lives:
In the wake of the battle against Master Xehanort and the ultimate triumph of the Guardians of Light, a sense of peace begins to settle over the universe.:
Mobius, too, is on its path to recovery and peace following Dr. Eggman's rule over the world. The citizens of Mobius begin rebuilding their lives and their world, as normality returns, albeit slowly.
Early 2018 - Current Timeline:
The Chaos Emeralds, powerful gems known for their connection to the Chaos Force, have mysteriously disappeared, leaving genius minds like Tails and Professor Pickle perplexed by their sudden absence.
The enigmatic circumstances surrounding the Chaos Emeralds have also captured the attention of Dr. Eggman, who, despite being in hiding, remains vigilant and scheming.
Unbeknownst to both the heroes and the villains, Eggman observed the climactic battle at the Keyblade Graveyard, gathering information and ideas to potentially further his own plans.
Sora remains missing, his selfless journey to save Kairi and the toll it took on him leaving a void in the hearts of his friends and allies.
This current timeline sets the stage for new adventures, challenges, and mysteries, as the characters from both the Sonic and Kingdom Hearts universes confront the unknown and work to unravel the secrets of their interconnected worlds.