One idea could be a story where the balance between the different dimensions overseen by Dialga (time), Palkia (space), and Giratina (the distorted world) is disrupted. Arceus, as the creator deity, has to step in. Maybe a powerful, unknown force is causing chaos, making time and space fold in on each other. Giratina, usually banished to the Distortion World, finds itself drawn back into the normal world, causing all sorts of mayhem. Dialga and Palkia try to fix things on their own but realize they need Arceus' help. The fanfic could focus on their journey to restore order and the sacrifices they might have to make along the way.
A plot twist could be that the powers of Dialga, Palkia, and Giratina are actually interchangeable. In a moment of extreme crisis, they merge their powers and identities, creating a new, super - powerful entity. This entity has the combined abilities of controlling time, space, and the distortion world. However, this also comes with a cost as they lose their individual identities. Arceus then has to decide whether to allow this new entity to exist or try to separate them back into their original forms.
The relationship can be explored through their power dynamics. Arceus is the creator, all - powerful, while Giratina is the banished one, yet has its own great power. Their interactions could start with Arceus trying to control Giratina's actions in the fanfiction, but Giratina resists. This power struggle can then evolve into a more equal relationship as they get to know each other better. For example, they might start to share their views on the Pokémon world and the balance of power within it.
Fanfiction about Giratina and Arceus can take many forms. Some may focus on epic battles between them, imagining different scenarios where their powers clash. Others might delve into their creation myths and how they are connected in the fan - created universe. For example, a story could explore how Giratina's banishment to the Distortion World by Arceus affected its personality and its view of the other Pokemon and the world itself.
Another theme is redemption. Giratina is an exiled Pokemon, and in many fanfics, its relationship with Dialga can be a path towards redemption. For example, Dialga may offer a way for Giratina to atone for its past actions through their connection.
Redemption is another common theme. Giratina, being banished, could be on a path of redemption in some fanfictions. It might try to prove itself to Arceus or the other Pokemon. This can lead to really interesting character development stories.
The theme of mystery is quite prevalent. Both Arceus and Giratina are shrouded in mystery in the Pokemon lore. Fanfictions often expand on this, creating stories where trainers or other Pokemon are trying to uncover the secrets behind these two legendaries. For example, stories might revolve around the origin of Giratina's exile and Arceus' true intentions for the Pokemon world. There are also themes of friendship and cooperation, where unlikely allies come together in the presence of these two powerful Pokemon.
There's a fanfic titled 'Dialga and Giratina: A Reconciliation'. In this, it starts with their long - standing differences. But as the story progresses, through various events and challenges they face together, they begin to understand each other more. It's really interesting to see how the author develops their characters.
Well, one interesting plot could be about the conflict between Arceus and Giratina being resolved in an unexpected way in the fanfiction. Maybe they have to team up against a common enemy that threatens their world.