For Kyogre, it could be characterized as a powerful but somewhat solitary being. It's protective of the oceans and views any threat to the seas as a direct attack. It's majestic and its movements are fluid like the waves. Groudon, on the other hand, is a force of the land. It's stubborn and proud, believing that the land is the most important part of the world. It's slow to trust but once it does, it's a loyal ally.
In a fanfic, Groudon can be seen as a proud and territorial being. Since it represents the land, it guards its territory fiercely. It has a sense of honor and dignity associated with its role as the keeper of the earth. Kyogre can be characterized as a wise and ancient entity. It has seen the ebb and flow of countless years beneath the ocean waves. It is patient but when provoked, it can call upon the power of the entire ocean to defend itself. They both can be shown as having a mutual respect for each other's power deep down, even though their natures often put them at odds.
One popular 'kyogre x groudon fanfic' is 'The Clash of Titans'. It really delves into the relationship between Kyogre and Groudon in a unique way. The story sets up an interesting scenario where they have to work together despite their natural enmity. It's full of action and also some great character development.
To develop Groudon's character, you could focus on its fiery nature. Show how it's not just about destruction but also about the renewal of the land. For Kyogre, emphasize its connection to the vastness of the ocean and its role in maintaining the balance of marine life. You could give them internal thoughts, like Groudon might be frustrated with always being seen as the one causing droughts, and Kyogre with being blamed for floods.
Well, it could be about their eternal struggle in a new light. Maybe in a world where they have to team up against a greater threat. For example, a new powerful Pokemon that is causing chaos in their shared ecosystem. Their powers combined could create a unique dynamic.
The potential for unique relationships. They can be rivals, but also in some fanfics, they become friends or even more. Their relationship can be explored in many different ways, like in some fanfics where they learn to understand each other's importance in the Pokémon ecosystem.
I'm not sure specifically as I haven't read that exact fanfic. But generally, a fanfic about Groudon and Kyogre might explore their relationship in the Pokemon universe. It could be about their battles, their coexistence, or some fictional scenarios where they interact in unique ways.
You can try looking on fanfic websites like FanFiction.net or Archive of Our Own. They have a large collection of Pokemon - related fanfics, so there's a chance you might find it there.
The theme of redemption can also be present. Maybe one of them has caused some kind of destruction in the past, and through their relationship with the other, they find a way to make amends. It could be Groudon's volcanic eruptions or Kyogre's tsunamis that they need to atone for, and their bond helps them in this journey of redemption.
There might be a story where Kyogre and Groudon are forced to work together. They start off as enemies but as the story progresses, they learn to respect each other's strengths. For example, Kyogre's control over water helps put out fires caused by Groudon's volcanic activities, and in return, Groudon provides land for Kyogre's sea creatures to rest on during low tides. This shows their growth from antagonists to allies in the fanfiction world.