In the fanfiction, Arcturus Black is likely an important figure in the wizarding world. He might be a powerful and knowledgeable wizard from the Black family. Maybe he has a long - standing reputation for his magical abilities and wisdom, which is why he is chosen to train Harry Potter.
Arcturus Black might be portrayed as a wizard with a deep understanding of ancient magic in the fanfiction. He saves Harry Potter perhaps because he sees in Harry the potential to defeat the dark forces that are plaguing the wizarding world. His character could be a blend of mystery, power, and a sense of moral obligation towards Harry.
In fanfic, it could be that Arcturus Black was a part of a secret society or had a mission that was related to the Potter family. He might have made some kind of pact or arrangement that made Harry his heir. It could also be a case of alternate timelines or universes where the normal rules of inheritance don't apply. Maybe in this particular fanfic's world, the magical laws are different and Arcturus Black's connection to Harry as an heir is a new and exciting concept.
First, do your research on the Black family and the wizarding world in general. Know the existing lore about Arcturus Black. Then, come up with an interesting concept, like exploring a relationship he had or a secret mission he was on. For example, you could write about his relationship with a Muggle - born wizard. Start with an engaging opening to draw readers in.
Well, Regulus Arcturus Black. He came from that very well - known pure - blood Black family. In the wizarding world, his family had a certain reputation. He got involved with the Death Eaters because of his family's inclination towards the Dark Arts. However, his conscience kicked in. He found out about the locket Horcrux. It was a dangerous mission, but he was brave enough to try and destroy it. His sacrifice in the end was quite heroic in a way.
The Death Eaters who still hold onto the old pure - blood supremacist views could be main antagonists. They might see the Heir of Arcturus Black as a threat to their ideology, especially if the Heir is trying to change the Black family's ways.
It might also mean that Harry inherits certain magical abilities or knowledge. Since Arcturus Black may have had his own set of skills and secrets, Harry as his heir could gain access to them. This could change the way Harry approaches challenges in the wizarding world, like fighting against Voldemort. He might have new spells or strategies at his disposal. Also, it could affect his relationships with other characters. Some might view him differently, either with more respect or with envy. And it could open up new plotlines in the fanfic, such as Harry having to deal with the expectations and responsibilities that come with being Arcturus Black's heir.
One great Arcturus Black fanfic could be 'The Legacy of Arcturus Black'. It delves into his family history and how it impacts the wizarding world. Another might be 'Arcturus Black: The Hidden Years' which explores the parts of his life that are not well - known in the official lore. And 'Arcturus Black and the Forbidden Magic' is also quite interesting as it shows his possible encounters with dangerous magic.
One interesting arcturus black fanfiction could be about his adventures during his school days at Hogwarts. It might explore his relationships with other characters like his family members or friends in a unique way.
One idea could be exploring how the Heir of Arcturus Black discovers hidden Black family magic. Maybe they find a secret chamber in the Black family home filled with ancient spells and artifacts. Another could be their interaction with Harry Potter. They might team up to fight against the resurgence of dark wizards in Hogwarts.