I don't know the specific 'stargate novel' so I can't say for sure. But usually there are brave explorers, scientists interested in the stargate technology, and maybe some military personnel to handle the security aspects.
Since there are many 'stargate novels', the main characters can vary greatly. In some, there could be a lead scientist who discovers new things about the stargates. There might also be a young and adventurous protagonist who is drawn into the stargate mysteries and ends up being a key figure in the story. Additionally, there could be alien characters that play important roles, either as friends or foes of the human characters.
I'm not entirely sure without reading it specifically, but it's likely to include characters from the Stargate Universe series. Maybe some military personnel, scientists, and adventurers who are part of the stargate exploration team.
I'm not sure specifically as it depends on the particular fanfiction. But often there could be a brave explorer type character who is eager to discover what lies beyond the stargate in Heliopolis.
Colonel Jack O'Neill is one of the main characters. He's a tough military leader. And then there's Dr. Daniel Jackson, an archaeologist who helps with understanding the different cultures. Samantha Carter, a brilliant scientist, is also a key character.
The main characters are likely to be a mix of the well - known figures from both the Sentinel and Stargate franchises. In the Sentinel side, Blair Sandburg might be there, given his importance in that universe. From Stargate, Teal'c could be one of the main characters. The fanfiction might also focus on some secondary characters from both universes and give them more prominence as they navigate the challenges of this crossover, like how they deal with the differences in technology and power systems.
I'm not sure specifically who the main characters are in this fanfiction without reading it. But it's likely to include some familiar faces from the Stargate franchise, like Colonel Jack O'Neill or Dr. Daniel Jackson. It could also introduce new characters created by the fanfic author.
Eli Wallace would likely be one of the main characters. He's smart and resourceful and has been important in previous Stargate Universe stories. Also, Colonel Everett Young, as the leader of the group, would probably play a major role in this 'Back to Destiny' story.
In 'War of Gods and Men Stargate Fanfiction', one of the main characters could be a young and determined human soldier. He is thrust into the war and has to quickly learn to survive and fight against the gods. Another main character could be a goddess who is conflicted about the war. She may have feelings for the humans and tries to find a way to end the hostilities. Also, there could be a brilliant scientist who discovers a way to use the Stargate in a new way to gain an advantage in the war.
One of the main authors is Bill McCay. He has written several Stargate novels that are well - received by fans.
For a 'harry potter stargate xover fanfic', Daniel Jackson from Stargate would be an interesting main character choice. His thirst for knowledge and understanding of different cultures would make him eager to explore the magical world of Harry Potter. On the Harry Potter side, Ron Weasley could be a main character. His loyalty and his ability to adapt to new situations could play a big role. And of course, Samantha Carter from Stargate with her scientific expertise could be involved in trying to figure out the scientific basis behind magic in the Harry Potter world if there is any.
Obviously, Harry Potter would be one of the main characters. From the Stargate side, Jack O'Neill could be an interesting addition. In the harem, Hermione could be there as she has always been close to Harry in the Potter universe. Also, a female Goa'uld could be part of the harem, bringing her own brand of power and mystery.