There are often stories where an original character in the fanfiction is a tech - priest who discovers a long - lost technology. This discovery sets off a chain of events as different factions, such as the Imperium and the xenos races, all try to get their hands on this new - found tech. It's full of intrigue, battles, and moral dilemmas as the tech - priest tries to decide what to do with the technology.
Another interesting concept is to have a Primarch face a completely new enemy. Not the usual chaos forces or xenos, but something from within the Imperium itself that has turned against it. This would create a lot of internal conflict and moral dilemmas for the Primarch to deal with.
The appearance and customization of Necron OCs can be really cool in fanfiction. They could have different color schemes or unique body modifications compared to the standard Necrons. For instance, an OC might have a more organic - looking part on their body as a remnant of their pre - Necron existence. Their personality also matters. A Necron OC could be more curious about the galaxy than the typical emotionless Necrons, leading them to explore places and engage in situations that normal Necrons wouldn't.
There might be a fanfiction where a group of Imperial Guardsmen encounter a Necron tomb world awakening. This story could explore the horror and confusion of the guardsmen as they face the ancient and powerful Necrons, and how they try to survive against overwhelming odds. It could also show the Necrons' view of the 'inferior' organic lifeforms.
There might be a fanfiction where a Primarch is reborn in a different era of the Warhammer 40k universe. In this story, they have to adapt to the new circumstances, which are very different from what they knew. They might find that the Imperium has changed in ways they can't fathom, and they have to fight new enemies and face new politics within the Imperium.
One interesting story could be about the rediscovery of an STC in a long - lost sector. It might involve a group of Tech - Priests on a quest to retrieve it and face various xenos threats along the way.
Some fanfictions might center around the battles between different Primarchs. For instance, the confrontation between Horus and Sanguinius. In these stories, the authors often delve into the tactical aspects of their warfare as well as the emotional turmoil of the Primarchs. Additionally, there are fanfictions that show the Primarchs interacting with normal Space Marines in unique ways, perhaps mentoring them or learning from them in some cases.
There are fanfictions that focus on the relationship between different Eldar Craftworlds. For example, a story where two Craftworlds must unite their forces against a sudden Tyranid invasion. This involves political intrigue as well as epic battles, with the Eldar using their psychic powers and advanced weaponry in creative ways.
One interesting story could be about a Space Marine who discovers the power of his Christian faith within the brutal and dark universe of Warhammer 40k. His faith gives him an extra edge in battle against the forces of chaos.
Some 'Warhammer 40k Tau' fanfiction might explore the Tau's attempts to convert other species to the Greater Good. This could involve diplomatic negotiations, battles, and moral dilemmas as they try to expand their ideology in a universe full of different beliefs and cultures.
One interesting fanfiction might be about Isha's role in the complex web of the Warhammer 40k universe. It could explore her relationships with other deities or her influence on certain races. For example, a story could focus on how she might secretly be guiding a group of Eldar through a difficult time, using her unique powers.