Well, Naruto would become extremely powerful. His combat abilities would likely be enhanced with the unique powers of arrancars. He could gain new forms and techniques. Maybe he'd have a zanpakuto-like weapon with special abilities, which would add a whole new dimension to his fighting style. Also, his speed and strength might increase exponentially, making him even more of a force to be reckoned with in the Naruto universe.
Naruto's character would likely become more complex. He'd have to learn to control the new arrancar powers, which could lead to some internal struggles. He might become more confident, or perhaps a bit more isolated as he tries to understand his new abilities. His values might also shift a bit as he experiences the different nature of arrancar powers compared to his regular ninja skills.
They blend by having Naruto use Arrancar techniques like the Hierro (the Arrancar's hard skin) in combat. He could use it to block powerful attacks from his enemies. This gives him an added layer of defense in addition to his normal ninja abilities.
If Naruto had Arrancar powers, he might gain the ability to use Cero, which is a powerful energy blast. This could replace his Rasengan in some ways, or he could combine them for an even more devastating attack. His movement would also become more like an Arrancar's, perhaps with the ability to move at high speeds in a more fluid and menacing way. And his appearance might change, with some Arrancar - like features, which would shock his friends and foes alike.
He could have the ability to use Sonido, which is a high - speed movement technique in the Arrancar world. This would make him much faster than normal ninjas. Also, his zanpakuto could have unique abilities, like the ability to cut through space - time, which would be a huge advantage in battles.
Well, it could be that Naruto gets some kind of elemental powers from the comet. Maybe the comet is associated with a new, rare element that Naruto can then manipulate. This new power could give him an edge in battles, as his opponents would be unfamiliar with it. He could use it in creative ways, like combining it with his existing jutsu to create even more powerful attacks.
Well, he'd probably be even more of a badass. His already formidable combat skills combined with Wolverine's healing factor and adamantium claws would make him nearly unbeatable. He could take on stronger foes without worrying much about getting hurt. And his speed and agility from his ninja training, along with Wolverine's berserker rage, would create a really interesting and powerful character in the fanfiction world.
Well, if Naruto gets Shinigami powers in a fanfiction, he could potentially gain the ability to manipulate souls. He might be able to use the Shinigami's scythe in combat, which would be a really cool and unique weapon. Also, he could have new forms of jutsu related to the soul realm.
Some fanfictions might give Naruto the power of elemental fusion. He could combine fire, wind, water, earth, and lightning in ways that are not possible in the original series. This would make his attacks extremely powerful and unpredictable. For instance, he could create a storm of lightning - infused water that not only electrocutes his enemies but also drowns them.
Well, Naruto could use his telekinesis powers in combat. He might be able to disarm his opponents without even touching them. Just by using his mind, he could send their weapons flying. For example, against Sasuke, he could stop Sasuke's sword attacks mid - air and then take the sword away from him. It would be a huge advantage in battles.