One possible fanfiction could be about a character with the powers of Phenex in the Naruto universe. They might use their unique abilities in combination with Naruto's own powers, like the Rasengan. When it comes to Amaterasu and Susanoo, perhaps this new character has to face off against an enemy who wields these powerful Uchiha abilities. The story could explore how the Phenex powers interact with the chakra - based abilities in Naruto's world, whether they enhance or conflict with each other.
Well, in such a fanfiction, it might start with Naruto finding an ancient artifact or meeting a strange being that gives him the Phenex power. Once he has it, he realizes he can integrate it with his existing jutsu like Amaterasu in the Susanoo. This new ability would attract all kinds of enemies and allies alike. He'd have to learn how to control it so as not to accidentally harm his friends. There could be epic battles where he uses this unique combination to defeat powerful foes.
A really interesting fanfiction concept could be that the Phenex entity is actually an ancient form of chakra that was lost in the Naruto world long ago. When it resurfaces, it starts to affect the balance of power. Amaterasu and Susanoo, which are already powerful and feared abilities, are now being influenced by the Phenex chakra. Naruto, being the hero, tries to find a way to bring back the balance. He could start by studying the history of the Phenex chakra and how it was used in the past. Along the way, he teams up with other characters who have knowledge about Amaterasu and Susanoo. They could exchange techniques and knowledge to combat the new threat that the combination of these powers poses to their world. This would involve a lot of world - building, character exploration, and exciting battles.
One idea could be a story where Naruto somehow gains the ability to use Susanoo. Maybe through some strange chakra experiment gone wrong or a gift from an ancient entity. He then has to learn how to control this new power while still maintaining his own ninja way.
A great fanfiction concept might be that Naruto somehow gains the Sharingan and Susanoo abilities. Maybe through some sort of experimental jutsu gone wrong (but in a good way). He then has to learn to control these new powers while still maintaining his own Sage Mode and Nine - Tails chakra. It would be interesting to see how he combines these different power sources to fight against new and old enemies.
One idea could be a story where Naruto somehow acquires the Rinnegan and combines its powers with the Susanoo. Maybe he has to face an extremely powerful enemy that can only be defeated by this new, super - powered combination. He could start by accidentally awakening the Rinnegan during a battle and then discovers that he can merge it with his Susanoo - like form.
Perhaps a story where a character from the Naruto universe, who has a connection to Amaterasu, travels to the Young Justice world. There, they meet a character who has a similar power but in a different form. They exchange knowledge about their powers and together develop a new technique that combines the elements of both their abilities. This new power could then be used to save both worlds from a common threat.
The abilities might be different too. Since Naruto has his own set of skills like the Rasengan and Sage Mode, his Susanoo could incorporate those elements. For example, his Susanoo's hands could form giant Rasengan - like attacks, or it could have the ability to enter Sage Mode, which would be a huge departure from the regular Uchiha Susanoo's abilities.
Well, in many fanfictions, Naruto might first awaken Susanoo during a really intense battle. Maybe he's pushed to his limits while fighting a super - strong enemy, and his latent Uchiha blood (if that's part of the fanfic's premise) gets activated, leading to the awakening of Susanoo.
There could be a fanfiction where a villain has mastered both the Mangekyou Sharingan and Susanoo in a way that no one has seen before. This forces the heroes to find new ways to combat this powerful foe, perhaps by delving into ancient jutsu that can counteract these abilities. It would be full of intense battles and strategic planning.
I'm not entirely sure as it's not a very common or well - known specific concept. It could potentially be a fan - made story where Naruto has some sort of connection or admiration for the Phenex, perhaps in a crossover or alternate universe scenario.