In Dark Magnus Bane fanfiction, a prevalent theme is his immortality. How he deals with living for so long and seeing the world change around him is often explored. Also, his interactions with other supernatural beings are a big part of it. Whether it's his clashes or alliances with vampires, werewolves or other warlocks. His flamboyant style and his sense of fashion might also be a theme that writers like to play with, adding some fun and unique elements to the stories.
One common theme is his magic and power. Writers often explore how Magnus uses his magic in different situations. Another theme is his relationships, like his romantic relationships or friendships. His backstory also features a lot, especially his experiences growing up as a warlock.
One common theme is the relationship between Magnus and those around him. His partner, whether it's Alec or someone else in some fan interpretations, might be shown as being very protective. Another theme could be the magical implications. Since Magnus is a powerful warlock, there could be speculations about how his magic is affected during pregnancy. And of course, there's the theme of anticipation and preparation for the new life, which might include things like creating a safe space in his magical lair for the baby.
One common theme is vulnerability. Since Magnus is often seen as a powerful warlock, these fics explore what happens when that power is stripped away, even if just temporarily, due to injury or emotional pain.
Emotional hurt is also quite prevalent. For example, his relationships with the Shadowhunters might cause him pain. Maybe a betrayal by someone he trusted, like Alec or one of the other characters, which can lead to a lot of angst in the fanfiction.
One common theme is the exploration of family. Since Magnus is pregnant, it often delves into how he and his partner (usually Alec) will form a new family unit and what that means for them. Another theme is the fear and excitement that comes with pregnancy. Magnus, being a warlock, has his own set of concerns about bringing a new life into the world, and this is often explored.
Love and acceptance are very common. Given that they are from different worlds (Shadowhunter and warlock), their relationship often involves them learning to accept each other's differences. Another theme is family. Alec has his Shadowhunter family and Magnus has his own kind of 'found family' among the Downworlders. Fanfictions often explore how their relationship affects and is affected by their respective families.
One common theme is the clash of different magical cultures. Magnus Bane comes from the Shadowhunters world with its own set of rules and magic, while Harry Potter has the wizarding world of Hogwarts. So, a lot of fan fictions explore how these two different magical systems interact. Another theme is friendship. Since they are both powerful in their own ways, they often form an unexpected friendship which is a central part of many stories.
One of the most popular themes is the exploration of their cultural differences. Magnus being a warlock with a long and rich history and Alec being a Shadowhunter from a more traditional background. Another theme is their struggle against prejudice. They face discrimination from the Clave and others due to their relationship. Also, the theme of sacrifice is common, like how they would sacrifice for each other's safety and happiness.
You can start by looking on fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions on various topics, including those related to Dark Magnus Bane. Another option is Fanfiction.net, which also has a wide range of works. Just use the search function and type in 'Dark Magnus Bane' to see what pops up.
One common theme is isolation. Magnus might be isolated due to his unique powers or past traumas, which causes him pain. For example, in some fics, his immortality makes him feel alone.
One common theme is friendship. Their relationship is often explored in depth, showing how they become close friends and rely on each other. For example, in many fanfictions, they help each other out during magical battles.