In this fanfiction, the Sharingan from the Uchiha clan is an obvious choice. It has so many abilities like the ability to copy jutsu and predict movements. Naruto could become even more of a prodigy if he absorbs it. Also, the Aburame clan's ability to control bugs could be quite interesting. Naruto could use bugs for reconnaissance or even in combat in ways that are different from his normal fighting style. And the Inuzuka clan's connection with animals, if Naruto could absorb that bloodline, he might be able to form a stronger bond with his summons or other animals in the wild.
Well, it could change the power balance significantly. If Naruto can absorb bloodlines, he might gain new and unique abilities. For example, he could absorb the Sharingan's power, which would give him enhanced visual abilities and maybe even some of the Uchiha clan's signature jutsu. This would make him an even more formidable opponent and could change the way battles play out. It might also create new rivalries or alliances as other characters react to his newfound powers.
A common plot element is Naruto initially stumbling upon the ability to absorb bloodlines, often by accident. For example, it could be during a fight or while exploring an ancient ruin.
Another good one is 'Absorbing Bloodlines: Naruto's New Path'. This fanfic focuses on Naruto's journey as he absorbs various bloodlines and how it affects his relationships with his friends and foes alike. The author does a great job of exploring the moral implications of Naruto having such a powerful ability, and it has some really cool action scenes.
In some fanfictions, one could be the Sharingan, which gives abilities like seeing chakra and predicting moves. Another might be the Byakugan, with its great vision powers. And the third could be something unique like the Ketsuryugan, which could have powers related to blood manipulation.
Maybe he uses some kind of special jutsu. It could be a new form of his shadow clone jutsu where the clones are able to analyze and then copy the bloodline traits of the opponents they encounter.
In the 'naruto has 3 bloodlines' fanfiction, these bloodlines can have a profound impact on the story. For instance, if one of the bloodlines allows Naruto to communicate with animals in a special way, it could lead to new alliances and ways of gathering information. A bloodline that enhances his ninjutsu in a unique way might make him the target of other villages or rogue ninjas who want to steal his power. And a bloodline that gives him the ability to heal others more effectively could change his role within the village from just a fighter to also a healer, which would completely shift the relationships he has with other characters and the overall direction of the story.
Well, in some Naruto fanfictions, a disease could be used to create a really unique plot. For instance, if a disease was created that specifically targeted the Kekkei Genkai holders. It would force the different clans to work together to find a cure. This would be a huge shift from the usual clan rivalries. Maybe the disease was created by a rogue ninja who wanted to wipe out all those with special bloodlines to gain power for himself.
Yes, it could be considered a relatively new concept as the amount and variety of fanfiction has exploded in recent years, and the idea of Naruto 'absorbing' these diverse fan - created ideas is something that has emerged as a result of the growing and evolving fan culture.