The Grand Temples of the Taiyoudama
By: Tellemicus Sundance
Heroes crossing Dimensions
-Avatar-verse-
When Amon created the Equalists, he chose Republic City for a variety of reasons. But the primary and most secretive reason is that during his early explorations of the world as he perfected his Bending Removal technique, he discovered that there once was a grand temple (Grand Temple of the Sun and Light) situated where Yu Dao (later Republic City) had been built during the era before the Avatar. This temple (hidden under the courthouse) supposedly held the power to open a gateway to the Spirit World and allow a person to travel to different worlds if they were able to gain a Spirit's approval. Amon wanted to find this gateway and travel to a new world to learn its secrets and bring back some new techniques and weapons for his crusade against the Benders.
When the Equalists discovered the temple while they were digging secret tunnels throughout the city, Amon soon learned that the gateway could only be opened when an Avatar was placed upon its entrance to become a literal Spirit Bridge. When Korra (17) made her announcement to duel Amon, he had her captured and brought to the gateway, using her to force open the gateway despite her lack of spiritual attunement and training. What he didn't expect was that because of her lack of training, she didn't form the 'bridge' but get dragged into it herself, throwing her across space and time (time in her dimension slowed to a stop).
-Naruto-verse-
Meanwhile, rumors spread of a dangerous, power-hungry ninja faction searching for an all-powerful ancient weapon that could allow them to seize control of the whole world. Dispatched to track down and deal with these rogue ninja, Naruto (firepower), Kiba (tracker), Ino (interrogator/medic), and Kakashi (leader) follow the clues and find the ninja gathered before a cave entrance to a large mountain in southern Rai no Kuni. After dealing with the guards, Ino interrogates one and learns that the weapon is apparently at the end of the cave system and that the main group had already gone inside.
Rushing into the cave, Naruto crashes into the main chamber where he finds himself in a trap. The rest of the team get incapacitated by surprise attacks while the rogue ninja take Naruto before a strange arch. The ninja boasts that his men had purposely spread the rumors of his group seeking a weapon to lure out the Jinchuuriki (any of them would've worked). This was because the arch was a highly chakra-intensive seal that would've drained any normal ninja dry and killed them without even activating. Despite their best efforts, the seals on the arch forcefully pulled Naruto and Kurama's chakra out and absorbed it. The gateway was opened. (After tumbling through the space/time for time immeasurable, Korra's chi was suddenly attracted to the opening of a new gateway and gets thrown into that world)
Unexpectedly for everyone, a few moments after Naruto opened the gateway, someone tumbled out of the gateway before the gateway closed itself off. As the rogue ninja tried to frantically reopen the portal, the newcomer awoke and attacked on instinct. Using the surprise of their captors, the Konoha-nin were able to break free and fight back, helping the newcomer to escape. Despite not understanding what they were saying, Korra could see that they weren't going to hurt her like the others and decided to risk it by going with them.
After escaping and reaching a reasonably safe spot, the ninja try talking with Korra but they quickly discover that they can't understand what she's saying, and vice-versa. Getting an idea, Ino uses her jutsu to implant knowledge of their language into Korra's mind, which knocks her unconscious afterwards. The ninja take her back to Konoha where she's given to the T/I corps, getting her mind read on whether or not she was a threat and to find out where she came from. What they find is too confusing to them to really understand, so Tsunade has taken to the hospital and placed under a watch.
After sleeping off the tremendous headache, Korra wakes up to find herself in the hospital of a strange village with strange people. She meets with several people, including the lady claiming to be the village leader. After a bit of storytelling, Korra is told of her arrival and that she's no longer on her own world. This causes her to become distraught and angry.
Needing to blow off steam, she goes out into the forest to Bend and destroy things. During her tantrum, several ninja approach her (including Naruto) and she gets into a spar with them. Interested in their fighting styles and abilities, Korra offers a trade: train her to walk on trees, water, and other stuff, and she'll teach them what she knows of Fire-, Earth-, and Waterbending. It was an offer that Naruto was quick to take. After several months of intensive training, several ninja were able to Bend like her and she was able to use some basic ninja skills.
When news of Jiraiya's death reached them, the Toads offered Naruto a chance to train in Senjutsu. But, to the surprise of everyone else, he also offered this to Korra since he could sense a tremendous well of Spirit Energy inside of her. Plus, he was certain that the Great Toad Sage knew how to return her to her home dimension. Korra was all-too-eager to accept his offer. While at the Toad Mountain, Korra was taught how to use natural energy and by consequence how to summon and control the Avatar State. When Pein attacked Konoha, Naruto left his training early to fight him while Korra spoke with the Toad Sage. From him, she learned the secret to returning to her homeworld was for someone of great chakra power (Naruto) to willingly reopen the portal and for her to jump and (theoretically) feel out her own universe's power and move to it.
After Pein's defeat, Korra talked Naruto into helping her return home. They (Korra, Hinata, Naruto, Ino, and Shikamaru) returned to the mountain and Naruto was able to reopen the gateway. But, like with Korra, Naruto's lack of training caused the gateway to fluctuate and pulled all of them in with Korra.
-Avatar-verse-
Returning to the Grand Temple of Sun and Light, Korra rushes outside to see what has happened to her world without her. She is dumbfounded to learn that it has only been three days since her disappearance after being caught by Amon. Shikamaru theorizes that whenever someone 'foreign' leaves their own dimension, time will automatically slow or stop until/if they're returned. With no rush to return to their dimension and nothing else to really do, the ninja (at Shikamaru's insistence) decide to 'tour' Korra's world. Korra takes them to the Air Temple where, after some frantic calming of Tenzin and the White Lotus, Korra relates her tale to them. During this, Ino uses her jutsu to implant Korra's language into each of the ninja minds so they can understand it better.
Waking up the next day with terrible headaches, the ninja are taken by Korra to tour the city.
Misc. Ideas
*Tenzin teaches Naruto Airbending
*Korra helps set Hinata up on a date with Naruto
*Ino becomes enthralled with Pro-Bending
*Shikamaru spends much time in the library, researching history, Satomobile mechanics, and other stuff
*Bolin becomes smitten with Ino after meeting her
*Naruto dons a disguise and hunts down the Red Monsoons after seeing them bullying some civilians, throwing them to the police where they get arrested. He becomes known as the Orange Twister due to his fighting style and Airbending
*The ninja help Korra fight back against Amon during his hostile takeover of Republic City