Well, in 'natsu is a dragon god slayer fanfic', themes like growth and evolution are very common. Natsu's character is growing not just in terms of power but also in his understanding of the world around him. Family is also a theme that pops up. Since dragons are like family to him in a way, his connection to them and how it affects his actions is explored. And of course, the theme of heroism. Natsu is seen as a hero, especially with his new powers as a dragon god slayer, and how he lives up to that role, facing challenges and saving the day, is a big part of these fanfics.
Power and responsibility is a common theme. As Natsu becomes a dragon god slayer, he has more power, but also more duties. Another theme is friendship. His friends in Fairy Tail still support him even as he changes. And there's often the theme of self - improvement, as Natsu has to master his new abilities.
One common theme is friendship. Their relationship as friends is often explored, like how they trust and rely on each other. Another theme is adventure. They usually go on some kind of adventure together, whether it's to defeat a new enemy or to discover something new. For example, in many fanfictions, they set out to find a lost magical item.
One common theme could be redemption. Natsu, being an outlaw, might be on a journey to redeem himself for past misdeeds. Another could be power struggles, as he is a dragon slayer and there might be others vying for power or trying to control him. Also, friendship might be a theme, as he could be making new allies even in his outlaw status.
In 'natsu x oc dragon slayer fanfiction', a frequently seen theme is the struggle against dark forces. Natsu and the OC team up to fight various villains and protect the world. Another common theme is family. In the Fairy Tail universe, family is important, and the OC may find a new family in the guild, especially with Natsu as a close friend or more. Additionally, the theme of growth, both emotional and in terms of magical power, is a staple in these fanfictions.
A lot of these fanfictions also deal with the idea of power and how they combine their dragon slayer powers. It could be them facing a powerful enemy and using their combined might to defeat it. There are also themes related to their pasts as dragon slayers, like how they overcame the loss of their dragons and how that affects their relationship.
One common theme is power and growth. As Natsu becomes a water dragon slayer, he has to learn to control his new powers, and the fanfictions often explore how he grows stronger. For example, he might face challenges that force him to adapt quickly.
One common theme is probably adventure. Lucy and the fire dragon slayer could go on quests together. Another might be friendship, as they develop a bond. And of course, there could be a touch of romance in some of the fanfics.
Power discovery is a common theme. Juvia often starts out not fully aware of her water dragon slayer powers and then has to learn about them. Another theme is friendship. As she grows as a dragon slayer, she makes new friends who support her journey.
One popular 'natsu is a dragon god slayer fanfic' might be 'Natsu's Ascent'. In this fic, Natsu's journey as a dragon god slayer is filled with intense battles and character growth. Another could be 'The Dragon God Slayer's Legacy' which delves into how Natsu's new powers affect his relationships with his guildmates. There's also 'Natsu: Dragon God Slayer Reborn' that takes a different turn on his origin story as a dragon god slayer.
One common theme is friendship. The Kamen Rider often forms strong bonds with other characters, and these relationships are explored in many fanfics.