Another place to look could be Naruto - dedicated forums. There are often sections where fans share their own fanfiction creations or recommend stories they've read. Some of these might include Magu Magu - themed fanfictions. You just need to do a bit of digging around in the different threads.
One interesting Naruto Magu Magu fanfiction could be about a new jutsu that combines the power of Magu Magu with another element in the Naruto universe. For example, a story where a character discovers how to merge Magu Magu with lightning to create a super - powerful attack. This would not only change the dynamics of battles but also the character's standing in the ninja world.
One idea could be a story where a young pirate discovers the Oca ate Magu Magu no Mi. They struggle at first to control the power of the fruit but gradually learn to master it. They use the powers to protect their crew from a powerful enemy.
One possible plot could be a character from the Naruto world obtaining the Magu Magu no Mi. They could then use the powers of the fruit, like creating and controlling magma, in battles against the Akatsuki. For example, imagine Naruto with the Magu Magu no Mi powers facing off against Sasuke. Naruto could use the magma to create barriers or launch powerful attacks, adding a new dimension to their rivalry.
In a fanfiction, the Oca ate Magu Magu no Mi might grant the ability to fly by creating a platform of fire beneath the user. This would add an extra dimension to the battles and the overall story. Also, the user could be immune to heat - based attacks from other sources, which would give them an edge in a world full of various powers.
If a character had the Magu Magu no Mi, it would likely disrupt the existing power balance. Their magma - based attacks would be difficult to counter for most ninjas who are used to dealing with chakra - based jutsu. This could make them a top - tier threat or a powerful ally depending on their alignment.
The plot could involve Naruto sharing his new power with his friends in Konoha. He could teach them how to work with the fire - based powers of the Magu Magu no mi. They could then develop new strategies for battles. For instance, Sakura could use her superhuman strength in combination with Naruto's new fire attacks to create a more powerful defense and offense for the village. Also, Naruto might have to hide his new power from some of the more traditional shinobi in the village who might be suspicious of this foreign power source.
In this fanfiction scenario, the Magu Magu Fruit could be connected to an ancient prophecy in the Naruto universe. Naruto is destined to find and consume it to unlock a new level of power. With the powers of the Magu Magu Fruit, he can not only fight better but also use the heat to heal certain wounds, as it has some unique restorative properties when used in a certain way. This would make him an even more important figure in the ninja world, and he would have to balance his new abilities with his ninja training.
One idea could be that the OC uses the Magu Magu no mi powers to protect a small island from a powerful pirate crew. The OC could create walls of fire to keep the pirates at bay and use the intense heat to disable their ships.
I think Sasuke would be really interesting. He already has a dark and brooding personality, and adding the power of the Magu Magu no Mi would make him even more formidable. He could use the magma to enhance his sword attacks, creating a molten blade or use it to create traps for his enemies. His Sharingan could also be used in combination with the magma powers to anticipate his opponents' moves better and launch more precise attacks.