One idea could be that Mega Man X and Nana team up to face a new, powerful enemy that neither could defeat alone. They have to combine their unique skills, like X's combat abilities and Nana's support functions.
Perhaps in the fanfiction, Nana gets corrupted by a virus and X has to find a way to save her without harming her. This could involve a journey to find a special antidote or a way to rewrite her corrupted code. It would show X's loyalty and determination to his friend.
Well, your OC could be a lost reploid from an ancient civilization. This OC might hold the key to a forgotten technology that could either save or destroy the world in the Mega Man X universe. They would have to navigate the politics and battles while trying to figure out their own origin and purpose. Also, an OC that was created by a villain but has a sense of good could be an interesting plot. This OC would constantly struggle between their programming and their new - found moral compass.
One idea could be a story where Bass has to team up with Mega Man X to face a new, extremely powerful enemy that neither could defeat alone. Maybe this enemy has the ability to corrupt the reploid's programming, forcing them to work together to find a cure as well as stop the threat.
One idea could be a crossover with the Sonic universe. Mega Man X and Sonic could team up to stop a new villain that is causing chaos in both their worlds. This would involve X's advanced weaponry and Sonic's speed working together in a high - action adventure.
One possible plot idea could be that Rock and X team up to face a new and powerful enemy that neither could defeat alone. For example, a super - advanced robot created by a long - lost mad scientist.
A really interesting Mega Man X fan fiction plot could be centered around a new type of Maverick that is immune to X's normal attacks. X has to go on a journey to find a way to upgrade his weaponry and adapt to this new threat. Along the way, he meets an old ally who has been in hiding and has some crucial information. Another plot could involve X being sent on a mission to a far - off planet where the Maverick virus has taken on a completely different form. He has to learn the ways of this new world to defeat the Mavericks there. And for the third one, we could have a story where X accidentally activates an ancient defense system that starts attacking both humans and Mavericks, and he has to find a way to shut it down.
Well, a plot could revolve around a young inventor in a parallel universe who discovers a way to communicate with the original Mega Man. Together, they try to find a solution to a virus that is spreading across multiple Mega Man universes, corrupting all the robotic beings. This would involve lots of action, as they have to fight their way through hordes of corrupted robots while also searching for a cure.
One idea could be that Mega Man X and Quake Woman team up to face a new powerful enemy that is causing earthquakes all over the world. They have to combine their skills, with X's speed and combat abilities and Quake Woman's power over seismic activity to defeat the foe.
One idea could be Mega Man traveling back in time to stop Dr. Wily from ever starting his evil plans. He could meet a younger version of Dr. Light and work together to prevent the future disasters. Another plot could be Mega Man accidentally traveling to a post - apocalyptic future where his actions in the past led to a world ruled by machines. He then has to go back and change things.
One idea could be that Megaman X and Nana team up to fight a new powerful enemy that threatens their world. They could combine their unique abilities to overcome various obstacles during the battle.
The relationship can be developed through shared experiences. For example, they could go through a tough battle together where they both have to rely on each other's strengths. This would build trust between them.