This chapter is a rewrite. So are the next two. In any case, I've updated this to fit a bit more into the canon universe, even though both worlds in this are AU, especially the first one mentioned. The main differences for the first one are that the Fourth is still Hokage, and there was no Uchiha massacre. The only real difference for the second one to this point is that Tsunade never collapsed, so Danzou couldn't take over. It's going to keep changing with the addition of the Fourth and the others, though.

In any case, I don't own Naruto, this is an unpaid side project that is just for fun and writing practise.

Worlds Will Collide

Chapter One – Advent

The evacuation of the civilians had been just in time. As soon as the last lot were out, he had appeared. Staring intently at his adversary, the Fourth Hokage frowned as the man stared back. Even though he was masked, Minato had the feeling that he was grinning at him. Shinobi were scattered around, fighting the white Zetsu creatures that had accompanied the man before him, the man with a sharingan and rinnegan eye each.

The man who called himself both Tobi and Madara drew a weapon, and Minato reacted in kind. They were already hours into their fight, something that had been interrupted a moment ago when the false Madara had absorbed all nine of the tailed beasts into himself, reconstituting the juubi, becoming its jinchuuriki. The moon he claimed to be using for some genjutsu was hidden behind thick cloud for now, and Minato was determined to end this before the jutsu could be enabled.

"Summoning jutsu!"

Instantly a giant toad appeared beneath Minato's feet, though his opponent remained unmoved.

"Summoning Gamabunta won't help you," Tobi sneered at him. "Now that I have become the host to the ten tails, there's no one who can stand against me."

"We will see about that," Minato spoke grimly, and attacked.

Tobi leapt backwards as Gamabunta's sword came crashing down towards them, forming hand-signs and unleashing a signature Uchiha fireball jutsu, which had the giant toad also dodging. Minato already knew that their opponent was an Uchiha, one they'd unfortunately never been able to identify. Not even with the Uchiha clan assisting them, which positively rankled at their sensibilities. Still, at least their cooperation had guaranteed their faithfulness to the village.

Focusing back on the fight before them, Minato released his own ninjutsu against his opponent, and for awhile, they traded their blows. Then, the clouds covering the moon parted and the light of its full form shone down. Tobi leapt away from him and stared up at it.

"It's time," he said, then looked back at Minato. "It's been great catching up, Minato, but now I have a world of peace to usher in."

Looking back up at the moon, he called, "Infinite Tsukuyomi!"

The moon flared red, and for a moment, Minato despaired. But then something strange happened. It turned white, then black, and a shudder engulfed the whole of the earth. At least, the earth he could feel. The night sky turned blacker, the stars blinking out at once. A deep purple shimmered through the sky, and lightning began to crash.

"What… What is happening?" Tobi demanded, his voice strained, and Minato swore he could detect a hint of fear.

Looking up, Minato saw that the moon was now that dark purple that had invaded the night sky, only it shone brighter. He noted that those white Zetsu creatures had stopped and were clutching their heads in agony. One by one they were burned up in intense black and purple flames, until they were all gone.

Two of his shinobi were immediate at his side then. "What is going on, Hokage-sama?" one of them asked.

"I do not know," Minato admitted, watching as Tobi now started screaming in agony as the Zetsu's had. "But I do not believe this is over. Something has obviously gone wrong with his plans, though I do not want to consider the possibility of what could be worse."

And yet that possibility seemed to be happening. Tobi was still screaming in agony, but now demon chakra was emanating from him, enveloping him like a cloak. He sensed in his opponent all the demons he'd ever encountered, and the ones he hadn't. In there somewhere was the nine tails, and Minato forced himself to push away his grief before he could even think of his son. He'd failed him back then, but he swore not to fail the village now.

"Attack formations!" he yelled. "We need to capture and suppress!"

"Hai!"

Together, Hokage and ninja worked side by side, but the overtaken jinchuuriki before them just kept getting stronger and stronger. Soon, the whole sky was the exact same shade and brightness of the moon, until it was almost impossible to distinguish the two.

Tails lashed out, sweeping away ninja like they weren't really there. Gamabunta attacked next, but the enemy shot a giant ball of energy at him, forcing him back. Minato was already weaving his own signs, casting his own elemental jutsu with his clones, and using rasengan as well. And yet everything they threw at the beast, nothing was actually damaging it.

"This seems to be a battle that we cannot win," Gamabunta puffed out, exhausted and nearing the end of his chakra summoning.

"And yet we cannot give in," Minato part agreed. "I may have to seal him with the shiki fūjin, but in order to do that..."

"In order to do that, he needs to be restrained first," Gamabunta intoned wisely.

"Exactly," Minato agreed. "I have no idea how to do it, though. He's too fast, more so than I am."

Even as he said that, the two of them had to dodge one of the tails aimed directly at them. It grazed Gamabunta, though, and the old toad grunted in pain.

"It may be best for you to go," Minato said. "We can handle this."

"Forget it, kid, I'm seeing this through," Gamabunta said, and accepting that, the two of them attacked.

Minato saw his people fight bravely beside him, even as he saw them fall as well. He was thankful for their presence, even as he wished that they weren't here to face this demon. The man known to them only as Tobi was gone now, a demon stood in his place. The destruction level was incredible, the entire village was now flattened, the Hokage monument destroyed with a huge crater in its place.

"RAAHHRGH!"

The cry of the juubi was heard far beyond Konoha's borders, waking people from their slumber as far away as River country. The last of the civilians who'd evacuated were close enough to feel the ground shudder with the call, as they themselves also shuddered with fear. Those ones hadn't yet made it to the assigned evacuation point, even though they were still nowhere near the battle. Their escorts and protectors were having quite a time keeping them calm.

Almost seven hours since Tobi had appeared, and an attack landing squared in Gamabunta's face had him forcibly unsummoned, causing Minato to stumble ever so slightly even as he fell at the sudden loss of his comrade. Knowing that he wouldn't be able to call Gamabunta back straight away, he charge into the battle alongside his fellow shinobi. No one could get a clear shot at the now massive juubi, its tails and cloak keeping them all at bay.

Suddenly there was another shift, and the juubi froze. Taking advantage of this, Minato leapt up to a clear vantage, and started to prepare the shiki fūjin. Before he could get it properly started, energy shot out of the juubi, and he had to dodge as some of it headed straight for him. Others were dodging too, but most of the energy seemed directed to the sky. Everywhere it hit, cracks instantly appeared. Space time was warping, Minato could tell, and it was expanding downwards towards them.

They were in serious trouble. Minato cursed and looked around, noting that most of the remaining shinobi also seemed to realise what was happening. Several ANBU joined him and asked, "Orders?"

"We need to get out of here," Minato told them.

There was no escaping, though. Everywhere he looked, the darkness was enveloping them. Minato could see that the blackness had expanded to the horizon, possibly beyond. He couldn't even guess at the damage being caused, and had this dark foreboding in the pit of his stomach that what they were witnessing was the end of their world. Space time was warping around them, they were all now frozen in place. Black flames appeared and began to spread, flames that were exactly like Amaterasu, that Uchiha specific fire.

"RAAHHRGH!"

Another cry from the juubi, and suddenly a burning sensation covered his entire body. Minato looked down in horror to see that his body was burning with a mixture of the Amaterasu and demonic fire. He was frozen in place, on fire and in immense pain. The juubi exploded then with a force he couldn't describe, and he saw everyone and everything around him disintegrate into nothing but ashes.

The last thing he saw as he looked up into the sky was the image of a three eyed, white face, and white haired woman grinning maniacally down at them.

OoOoO

It was just another day in the village of Konohagakure, and Uzumaki Naruto, the resident knuckle-head, was headed off to meet his team mates. They were helping with the rebuilding of the village after Pein's attack on it, and Team Kakashi had been assigned to the east section of the village. Tsunade had teams of gennin and chuunin assigned to helping with the rebuilding, as most jounin and several ANBU were out on missions to bring in revenue for the village. This would have meant that Kakashi and Yamato would be off on missions, but for the moment they were free to help out.

"Alright!" Naruto said as soon as they'd reached their destination. "Let's get this going!"

"Naruto!" Sakura chastised. "You don't even know what we have to do yet! We need to find the foreman of this section."

"That would be Hasegawa Juro," Yamato said. "Over here."

Juro was a tall, bushy haired, and beefy man who immediately set them to clearing through debris. "We saved all of this for the ninjas," he said. "Us civilians can't get into the really heavy rubble in here like you guys can."

"Just leave it to us, Juro-san," Sakura said even as Naruto created several clones who cheered at the thought of helping out.

"That's him, isn't it?" Juro said. "He's the one who saved us all from the Akatsuki."

"He sure is," Kakashi said as he watched Naruto bet Sai he could clear more rubble, which the former ROOT ninja ignored.

"I died, you know," Juro said. "Explosion knocked me back and I guess I must have broken my neck or something. Came back in the middle of my wrecked house."

Kakashi nodded, knowing the feeling as he'd been among those resurrected too.

They all worked hard for a few hours, Yamato having to leave at one point to help put up some new structures with his wood style ninjutsu, but he came back once that was done to help out again. Lunch rolled around and they stopped to eat before getting back into the work. Finally, they'd cleared as much as they could, making it safe for civilians to go through instead.

"I'm headed back to the Hokage's tent to see what's next on the agenda for us," Yamato said. "You guys should go get lunch, rebuild your energy."

"Alright!" Naruto cheered once Yamato was gone. "Ichiraku ramen, here we come!"

"Did you forget that Ichiraku's was destroyed?" Sakura reminded him.

"Yeah, but old man Teuchi has opened a temporary stall to help feed people," Naruto told his team mate. "C'mon Sakura, Sai, Kakashi-sensei!"

Suddenly Naruto froze. "What is it?" Sakura asked. "What's wrong?"

It was then that she sensed it too, as well as Sai and Kakashi.

"What is that Kakashi-sensei?" Sakura asked.

"I don't know," the silver haired jounin said, "but it can't be good."

All of a sudden Naruto took off towards where the Hokage was coordinating the village repairs. "Naruto!" Sakura called, and his three team mates were off after him.

Over at the temporary Hokage office, which was little more than a tent at this point, she and her assistant were outside, staring at the sky. "What's going on, Tsunade-sama?" Shizune asked, holding a terrified Tonton in her arms.

"I don't know," was the reply. "Aoba! Raido!"

The two jounin appeared seemingly out of nowhere, though they had been nearby as they were on duty as the Hokage's 'emergency jounin'. "Hokage-sama!" they saluted in unison.

"See if you can find out what's going on!" Tsunade ordered, and they left immediately just as Team Kakashi appeared on the scene.

"Baa-chan!" Naruto yelled as soon as he spotted the Hokage. "Can you feel that?"

"Of course I can feel that, I'm not a dolt!" Tsunade snapped. "It's some kind of chakra…"

"Its demon chakra," Naruto interrupted.

"What?! How can you tell?" Sakura asked.

"I'm not sure. All I know is that the kyuubi recognised it and tried to warn me just before anyone else noticed," Naruto told the Hokage. "It said there's only been one demon with that chakra signature, and it's impossible for it to be here, since it was dispersed!"

"What?!" several people spoke in shock at once, then Tsunade forced herself calm.

"Alright," she said, "first we need to…"

"Hokage-sama!" Raido was back. "There's something happening over at the Academy training grounds!"

"What is it?" Tsunade demanded, ignoring the fact that she'd been interrupted, considering the circumstances.

"Some sort of spatial disturbance," said Aoba, who appeared behind his comrade. "The sky has turned dark as well, even though it's the middle of the day."

Tsunade was instantly alert and on the way, Shizune put Tonton back in the tent, telling the pig to stay put, then she followed her master. Aoba, Raido and Team Kakashi were also hot on the Hokage's heels. Sakura kept a close eye on her mentor, knowing full well she wasn't back up to her best after using her jutsu.

Even before they reached the Academy, the darkness that Aoba had mentioned had already started spreading through the village, and once they actually reached the Academy, it had encompassed the sky as far as the sharpest shinobi eye could see. That oppressive chakra presence and an eerie chill accompanied the phenomenon.

When they reached the partially ruined Academy, it was to find the large distortion hovering in the air, slowly spreading out with the strange darkness. Kakashi immediately exposed his sharingan to see if he could analyse it, even as Tsunade began yelling at all the Academy students that were here to help with repairs and had ignored their sensei's to come see what was happening.

"It's definitely a space time portal of some sort," Kakashi said. "A lot like my kamui… Rather disturbingly like it, actually."

More and more shinobi had been drawn in by the phenomenon, including ones like Nara Shikaku, Inuzuka Kiba, Tenten and others, their stances tense and battle ready. But civilians had noticed the phenomenon as well, they'd have to have been blind to miss the darkened sky. A lot of people were afraid that the village was under attack again, though nothing except the warping sky seemed to be happening, at least physically. There was still the oppressive demon chakra, after all.

Many people jumped suddenly when lightning cracked across the sky, causing thunder to roar. The shinobi gathered at the Academy, which seemed to be the epicentre, all tensed as the space around them began to shimmer like heat coming off a surface during the hotter months. And indeed, there seemed to be heat radiating all around them. Slowly figures began to appear, ones that began to take the shape of people. Another loud crack of thunder and all of a sudden the forms materialised into actual people.

There was a tense moment as the Konoha shinobi realised that the newcomers were shinobi as well, until one of them was recognised. "M-Minato-sensei?" Kakashi stuttered at the sight of his long dead sensei standing there before him.

But the Fourth's eyes weren't on Kakashi, instead they were on the blond Uzumaki. "Naruto?" he whispered, and then he collapsed in a dead faint, along with all the others that had turned up with him.

So how was it? I think I didn't do too badly redoing this. Review please!

Shiki fūjin: The demon sealing jutsu.