Well, perhaps in this fanfiction, Natsu was held captive by a dark force for a long time, which prevented him from joining Fairy Tail earlier. When he does join later, he has a deep-seated anger towards the forces of evil. He becomes a sort of wild card in Fairy Tail, his actions often driven by his thirst for revenge against those who wronged him, but also slowly learns to fit into the guild's friendly and family - like atmosphere.
In a 'natsu joins fairy tail later fanfiction', it could be that Natsu was on a self - discovery journey before joining. He traveled around the magical world, learning about different magics and cultures. When he finally decides to join Fairy Tail, he brings with him a wealth of knowledge. This makes him both an asset to the guild in terms of fighting power and also someone who can teach others about the things he has learned. For example, he might know some ancient spells or ways to deal with certain magical creatures that the other Fairy Tail members were not aware of.
One possible plot could be that Natsu has been living a different life away from Fairy Tail. Maybe he was raised by another guild unknowingly. When he finally joins Fairy Tail later, he has to prove himself to the existing members who are skeptical of his late arrival. He might have unique magic skills he developed elsewhere that surprise everyone.
Well, one possibility is that Natsu could join Fairy Tail in a different way than in the original story. Maybe he has some special mission before officially becoming a member. For example, he has to prove his loyalty by helping an elder member with a personal problem.
One possible plot could be that Natsu and Mirajane join Fairy Tail at different times. Natsu might bring his usual enthusiasm and powerful fire - based magic. He could quickly get into all sorts of adventures, making friends and enemies alike. Mirajane, on the other hand, could use her Take - Over magic to be a great asset in battles. Their joining could lead to new team - ups within the guild, like Natsu and Mirajane going on a mission together to stop a dark wizard who is causing chaos in a nearby town. They'd face challenges, but their combined skills would help them overcome the odds.
It could be a powerful wizard who has a grudge against Fairy Tail and sees Natsu as a new threat. This wizard might have been secretly observing Fairy Tail for a long time and when Natsu joins, they decide to strike. Their magic could be something unique like shadow manipulation or time - based spells.
Perhaps an old enemy of Fairy Tail who sees Natsu as a new threat. They might target Natsu specifically to prevent him from strengthening the guild. This antagonist could have a long - standing grudge against Fairy Tail and see Natsu as the new hope for the guild, so they try to eliminate him before he can fully join.
In such a fanfiction, Natsu might have become much stronger. Maybe he has mastered new fire - based magic techniques. He could also have new relationships within the guild, like closer friendships or even a romantic interest.
The plot could involve Kagome bringing her spiritual powers and archery skills to Fairy Tail. Maybe she'd form a team with some of the guild's mages and go on adventures. She could use her holy powers to combat dark magic threats in the Fairy Tail world.
The plot might revolve around Yukino's journey of self - discovery within Fairy Tail. At first, she might feel like an outsider, but as she gets involved in the guild's daily activities, she starts to find her true self. For example, she could participate in the Grand Magic Games as a representative of Fairy Tail. During the games, she showcases her skills and also learns about the value of teamwork and friendship within the guild.
One possible plot could be that Acnologia, with his immense power, initially causes chaos within Fairy Tail. The members are both in awe and afraid of him. But as time passes, he starts to understand the concept of friendship and loyalty in Fairy Tail. He could then use his power to protect the guild from other major threats, like the Alvarez Empire. This would completely change the power dynamics in the Fairy Tail world.
It could be about Natsu having left Fairy Tail for some reason and then reuniting with the guild in a very unexpected way. Maybe he has new powers or a different outlook on life that causes some friction and also some amazing moments of reunion and growth within the guild.
It could be a powerful dark wizard who has a grudge against Fairy Tail. This wizard might see Natsu and Mirajane's joining as an opportunity to strike at the guild when it's in a state of flux. He could be someone who was once defeated by Fairy Tail in the past and has spent years building up his power for revenge.