Disclaimer
Understand that I have changed some facts that were known in cannon such as that for that sake and purpose of this story I will claim that Tobi is actually Uchiha Madara
I do not own Naruto or Bleach
Ch1 The beginning
It seems it has been twenty thousand years, since I killed that Uzumaki brat, since I became a god. Unfortunately it appears my time is up, after all these years Sasukes' eyes are losing their light. Izuna I hope you're happy, I did as you asked.
Madara Uchiha looked up from his view of the blue ocean, to see the sky above, however instead of the usual black and red, he notices cracks spreading all throughout the heavens.
How times have changed hm, the shinobi era ended with ash
and now cities are starting to bloom all around while I have been governing this earth as its sovereign. No wars, no bloodshed since I came to power, however I am glad my reign is coming to an end after all there is nothing left for me to do.
500 years Later- Karakura Town
"Hurry up Ichigo their is a hollow nearby", "I'm coming give me a sec", As Ichigo popped a pill in his mouth, his body seemingly collapsed while his reistu stormed out of his body, condensing into a spectral form, then expanding into his shinigami form, I am ready Rukia lets go. A quick shunpo later and the duo came into view of a giant monster, looking like a cross between a bull and an octopus however its oddest characteristic is that there is a hole where its heart was supposed to be. As Ichigo charged at the monstrosity at full speed, wanting to finish it off quickly he was immediately dispatched by one of the beasts' eight tentacles. Rukia, seeing Ichigo seemed down for the moment, took a second to determine the beasts strength," What is this thing its reistu seems so dark, I can't move", Rukia saw images of a dark skinned man, with multiple swords talking to a blond haired boy, then everything changed, and she saw all of these other monsters, a one tailed raccoon and a nine tailed fox fighting what seemed to be a ten tailed wolf, with a massive eye on its head. As the beasts were about to strike, everything went black.
But before she hit the floor, Ichigo instantly appeared besides her. "What happened to her, why did this happen"? As Ichigo was pondering this dilemma, the eight-tailed hollow, screamed a wretched wail, summoning up what seemed to be a portal and quickly fled. "What was that about, I can't help but feel anxious, after all Azien should be coming here soon to summon a portal to the soul king, killing everyone in sight". "Which is why I need to stop him. But first I need to take Rukia home to rest".
At the Kurosaki Residence
Oh Ichigo-ni why are you carrying that girl, huh, where are you taking her? Don't worry about it Karin, I'll take care of it. Quickly shutting the door, Ichigo lays Rukia down on his bed. Seeing her chest rise and fall, Ichigo sighs, I won't let anything happen to you Rukia, you are precious to me. Ichigo wraps Rukia up in a blanket and lies down next to her dreaming content dreams of friendship and love.
A week later- Above Karakura Town
A portal opens up, tearing even the sky apart, and five figures are seen walking out. The blond one yells, "Aizen are you sure we can do this"?" Don't worry, I have complete faith in the hygoku". Aizen-samma don't you think you should have a back up just incase I mean it is the shinigami elite we are fighting after all, "Stark, don't worry my plans always work". Just as Aizen finished speaking, he felt a reistu spike and then saw multiple figures appear on the other side of the clearing, "their here, everyone hold still", commanded Aizen.
"So which one is the strongest"? Asked a brute of man, "Kenpachi, Aizen leads all of these abominations so he is then most likely the strongest." "Shut up Ichigo I don't need you being all smart on me now Strawberry". Ichigo being offended, replied "Kenpachi you moron my names Ichigo",
Ignoring the chaos. Aizen quickly announced his victory, "All of you shinigami. Have. Lost. For I am god". Aizen then disappeared from view, and destroyed the spiritual support towers that were on the four corners of Karakura town.
The shinigami were astounded and all wondered, "How did Aizen know that the towers kept Karakura safe"?
As quickly as the towers were destroyed, the scenery changed, it seemed as reality was torn asunder, and then a new reality was conjured up and the real Karakura town emerged.
As soon as Ichigo realized that his home was in danger, he charged Aizen, "Aizen you will not harm a soul in this city", as Aizen raised his hand, Ichigo charged up his bankai, and black reistu soon coated his blade, while Aizen kept his hand in the air, Ichigo charged, Then Aizen brought his hand down, and spoke " I will destroy everything and recreate create it anew, for I am your savior, I am your god, " When Aizen finished his dialogue Karakura town was sent ablaze, the force of his hand falling from the air caused shockwaves to spread across the city like massive earthquakes and unavoidable hurricanes, killing and ravaging the townspeople. The shinigami including Ichigo, just stood their in shock, taking in Aizens' power, but before they could even blink, Aizen was focusing reistu again, The head captain widened his eyes, he charged with his blade creating flames so hot that it burned the air around, "No! Yamamotto, Aizen is to strong don't go "his fellow Shinigami screamed, and as Yamamotto approached Aizen a torrent of energy whirled around him, protecting him from all attacks, Yamamotto screamed," Aizen let me burn you to bits"! Aizen calmly replied "its over captain, its always been decided that I would win, for I am superior to all." Suddenly the sky was torn, a ripple of energy turned into a miasma of power ripping the very fabric of space, and a single figure came down.
And then chaos began, the seemingly harmless blond haired youth that spoke with Aizen earlier screamed with fury, "Madara! I will kill you", Aizen sensing his followers fury, thought, " how does Naruto know the shinigami king? He is so weak compared to me" The now named shinigami king, looked around and spoke,
"Naruto Uzumaki do not worry time has changed me, I now understand war is more essential than peace". Naruto stood their frozen in shock, not understanding Madaras' words. Then Aizen charged Madara and tried to cut the shinigami king and take his place, however to his shock his blade went straight through Madaras' body as if he was a ghost, and then Madara spoke, "I am above you Aizen Sosuke, for I am Uchiha". And as quickly as his words left his mouth, Madara made what seemed to be hand signs and then he put his hand on the ground and spoke "Mokuton Hijustu: Jukai Kotan". As his words left his mouth, life started to grow, at a rapid rate, trees grew and then a forest was born. All of the beings present stood their wondering what was happening and if that was all the power the shinigami king held, Aizen taunted, " Is that all you can do shinigami, "You don't deserve to have power, for you are a fake King". Madara just smirked and then the trees exploded with raw power, growing and twisting, and effectively trapping Aizen in a veritable forest. Madara pursed his lips, making more hand signs, and then sucked in air, all of a sudden the blond haired hollow spoke, "Aizen guard yourself". Aizen noticed a massive increase in power from his opponent and began to worry, but before he could move Madara whispered "Katon: Karyu Endon", causing an immense fire dragon to form, charging at Aizen. Aizen noticing he was in danger tried to move but found he was rooted in place by the surrounding foliage. As the flames hit, the massive forest that Madara created, they burned everything to ash.