One great 'no devil fruit Luffy fanfiction' is 'Luffy's True Strength'. In this story, Luffy focuses more on his Haki training and martial arts skills. He forms unique alliances with characters from different islands based on his pure strength and charisma, without relying on devil fruit powers. It shows a different side of Luffy's leadership and combat abilities.
A popular 'no devil fruit Luffy fanfiction' is 'Luffy's Natural Growth'. This story delves into how Luffy would develop if he didn't have the Gum - Gum powers. He becomes an expert in acrobatics and uses improvised weapons from the various islands he visits. His crew also adapts, with Usopp creating more unique weapons for him, and Nami devising strategies that play to Luffy's non - devil - fruit - enhanced strengths.
There's a fanfiction called 'Luffy, the Haki Master'. It's set in an alternate universe where devil fruits don't exist. Luffy has to rely solely on his Observation Haki, Armament Haki, and his inborn tenacity. He goes through intense training regimes with Rayleigh and masters his Haki to a level that allows him to take on the toughest foes in the Grand Line, all while maintaining his goofy and lovable personality.
One interesting idea could be that Luffy has to rely solely on his Haki and physical training, making him even more of a badass in combat. He might develop unique fighting styles that we haven't seen in the original story where he had devil fruit powers.
If Luffy ate a different devil fruit, his entire power set and character would change drastically. For example, if he ate a Logia type like the Smoke - Smoke Fruit, his fighting style would be more about evasion and stealth. He could turn into smoke to avoid attacks, and his stretching abilities would be gone. His crew might also have to adjust their battle strategies around his new powers.
In some fanfictions, Luffy's Devil Fruit is indeed considered the strongest. His Gum - Gum Fruit gives him unique abilities like stretching his body in incredible ways. In fan - created stories, these abilities can be enhanced even further, making him almost unbeatable.
One interesting idea could be that Luffy's dragon devil fruit gives him the ability to control different types of weather related to dragons, like summoning thunderstorms or creating strong winds. Another could be that he gains the power to transform into a dragon - like form with enhanced strength and speed.
Imagine Luffy ate a devil fruit that gave him the power to control minds. This would be a very different power compared to his current Gum - Gum abilities. His crew would have to trust him completely not to abuse this power. There could be ethical discussions within the crew. Also, in terms of leadership, Luffy might have an easier time getting others to follow his plans, but it could also create some tension if the crew felt he was relying too much on his mind - control powers instead of his natural leadership qualities.
The uniqueness of 'no devil fruit Luffy fanfiction' lies in the fact that it challenges the traditional view of Luffy. Without his devil fruit powers, Luffy has to rely on his other qualities like his determination, his Haki, and his physical combat skills. It's interesting to see how he overcomes challenges in a different way.
Another possibility is a Devil Fruit that gives her the power of telepathy. Fem Luffy could then communicate with her crew without speaking, which would be very useful in stealth missions. She could also use it to read the minds of her enemies, getting an edge in battles. This would completely change the dynamics of her relationships with other characters in the story as well.
One interesting plotline could be Luffy struggling to control the new powers at first. Since Logia fruits give the user the ability to become an element, Luffy might accidentally turn into his Logia form at inopportune times, causing chaos among the crew. For example, if his new power is related to fire, he could set the sails on fire by accident while trying to learn how to use it.
Sure, in fanfiction there are no real limits. Luffy might survive eating another Devil Fruit if the author decides to create a new mechanism. For example, there could be a magical item or a rare fruit that cancels out the negative effects of consuming multiple Devil Fruits. Or perhaps his strong willpower and unique body constitution, which already allowed him to adapt to the rubber Devil Fruit, could also help him handle a second one.
One of the main things that make it strong in fanfiction is the creative use of its basic properties. Writers can make Luffy use his stretching in ways that are not shown in the original manga or anime. He could stretch his internal organs to survive otherwise fatal blows. Or he could use his stretched body to create complex structures for defense or to launch multi - directional attacks. This freedom of creativity in fanfiction enhances the perceived strength of his Devil Fruit.