Perhaps in the ancient times, there were different rules for Digimon evolution. You could write about a Digimon that discovers an ancient form of evolution that was thought to be lost. This Digimon then has to deal with the consequences of this new - found power. It might be hunted by other Digimon who are afraid of this change or might be revered as a sort of savior by some. This would create a complex and engaging story line.
A great plot could involve a hidden power in the ancient Digimon world. For example, a long - lost artifact that gives the possessor control over all Digimon. The story could follow a group of young Digimon and their human partners as they search for this artifact, facing many challenges along the way from other Digimon who also want the power for themselves. This would add a lot of adventure and mystery to the fanfiction.
A plot could involve a group of dark digimon forming an alliance to take over a particular area of the digital world. They start by targeting the weakest digimon settlements. The story could follow a young digimon trainer who tries to gather allies to fight back against this dark alliance. There could be many challenges along the way, like finding rare and powerful digimon to join the cause, and also dealing with the psychological warfare that the dark digimon use. For example, they might spread false rumors to cause distrust among the good digimon.
One idea could be an OC who has a unique bond with a Digimon that's not a typical partner. For example, an OC who can communicate with wild Digimon and uses this ability to stop an evil force from disrupting the Digimon world. Another plot could involve an OC Digimon Hunter who discovers a hidden power within themselves during a dangerous mission. Maybe they can temporarily fuse with their Digimon partner to gain super strength and defeat a powerful enemy.
A plot could revolve around a digimon human hybrid who discovers they have a unique digivolution ability. This ability might be a key to unlocking a hidden power within the digimon world that could either save or endanger both the human and digimon realms. Maybe this hybrid is initially ostracized by both humans and digimon for being different, but as they uncover the secrets of their power, they gain acceptance.
One idea could be that the Pokeballs and Digivices somehow get mixed up. So trainers start finding Digimon in Pokeballs and vice versa. It would lead to a lot of chaos as they try to figure out how to handle these new creatures. Another plot could involve a villain who wants to combine the power of Pokemon and Digimon for evil purposes, forcing the heroes from both worlds to team up.
Maybe there's a situation where the Digimon from both series start to lose their powers for some unknown reason. The characters from Digimon 02 and Tamers must journey together to find the source of this problem. They could encounter old enemies and new threats along the way. The Tamers' more technical knowledge and the Digimon 02 gang's experience in the digital world could be key to solving the mystery.
One idea could be the Digimon characters getting lost in Wonderland. They might encounter the strange creatures of Wonderland and have to figure out how to get back to their own world. For example, Agumon could meet the Cheshire Cat and have a confusing conversation about directions.
One idea could be a story where the Digimon from the Black Star series team up with Digimon from other series to fight a new, powerful enemy that threatens all the Digital Worlds. They would have to learn to combine their unique abilities and overcome their differences.
One interesting plot idea could be the Digimon characters getting transported to a different digital world during the events of Summer Wars. They could encounter new types of Digimon and have to form alliances to survive. Another idea is that a human character from the Summer Wars universe somehow gains the ability to enter the Digimon world and has to learn how to control their newfound powers. Maybe a group of Digimon come to the human world during Summer Wars and cause chaos, and the main characters have to figure out how to send them back while also dealing with the normal chaos of the Summer Wars event.
One idea could be the main character using gamer skills to quickly level up their Digimon in unexpected ways. For example, finding glitches in the Digimon world that allow for super - fast evolution. Another could be a tournament - style story where the gamer - like abilities of the protagonist give them an edge over other Digimon tamers.
One idea could be that the Digimon and Pokemon worlds collide due to a strange rift. The main characters from both universes have to team up to close the rift. For example, Ash from Pokemon and Tai from Digimon could lead their respective teams. They would encounter challenges like Digimon getting lost in the Pokemon world and vice versa, and have to figure out how to communicate and work together to solve the problem.