In some fanfiction, Hiccup discovers a long - lost dragon training technique. This leads to him and Toothless developing an even stronger bond and being able to perform incredible feats together. They then share this new knowledge with the rest of Berk, changing the way dragon training is done.
There might be a fanfiction where Hiccup, as the dragon master, has to train a group of young dragons and their riders. It could involve a lot of challenges like dealing with the different personalities of the dragons and the inexperience of the riders. He uses his unique bond with Toothless to inspire the others.
One interesting story could be about Hiccup exploring a new, uncharted island with Toothless and encountering a rare, magical dragon species. They have to figure out how to communicate with it and earn its trust.
Good characterizations. When the author gets Hiccup's character right, as well as the dragons. They should feel like the ones from the movies but also have some new aspects. For instance, if Toothless has a new power that he discovers in the fanfic. Also, the relationships between the characters should be well - developed.
You can try fanfiction websites like Archive of Our Own (AO3). It has a large collection of HTTYD fanfictions. Just search for 'Hiccup dragon master' and you'll get a bunch of results.
I really liked 'A Dragon's Bond'. It delves deep into the relationship between Hiccup and Toothless. There are a lot of emotional moments, like when they face a really tough challenge together and their bond is put to the test. It also has some cool new dragon designs.
A major theme is power and responsibility. When Hiccup transforms, he gains new powers. In these fanfictions, he usually has to figure out how to use them for good and not let the power corrupt him. Friendship is also a big part. His friends' reactions and how they support or struggle with his new form is often a key element. And there's the theme of identity. Hiccup has to re - define who he is in the context of being part - dragon.
A more complex plot could be that a dark force is corrupting the dragons, and Hiccup, as the Dragon Master, has to find the source of this corruption. He has to use his skills and the bond he has with his dragons to not only stop the corruption but also save the dragons that have already been affected.
One popular 'HTTYD Hiccup is a Dragon Shifter' fanfic could be 'The Dragon Within Hiccup'. It explores how Hiccup's new ability as a dragon shifter changes his relationship with Toothless and the other dragons. Another might be 'Hiccup's Shifting Destiny' which delves into the challenges he faces while hiding his new form from the village at first.
A great HTTYD half - dragon fanfiction could be centered around a half - dragon's discovery of their heritage. They are raised as a normal human in a Viking village but start to notice strange abilities. As they explore their dragon side, they find a long - lost dragon family and must decide whether to stay with their human family or embrace their newfound dragon kin. Along the way, they use their half - dragon abilities, like being able to communicate with dragons on a deeper level or having enhanced strength and speed, to protect both their human and dragon families from common enemies like dragon hunters.
In some 'httyd oc dragon fanfiction', an oc might be from a different tribe that has a completely different way of training and living with dragons. The story could detail the cultural differences and how the oc's perspective on dragons changes when they interact with the main characters from the known 'httyd' world.
There's also 'Hiccup's Dragon Metamorphosis'. In this fanfiction, the author focuses on the emotional aspect of Hiccup's transformation. It delves into his relationships with Toothless and the other Vikings, and how his new state affects those bonds. It's really interesting as it gives a deep look into Hiccup's internal struggles.
One interesting plot idea could be Hiccup and Astrid going on a secret adventure to a new, uncharted island. They face new dragons and have to work together to survive. Another could be a story where they have to deal with a rift in their relationship due to a misunderstanding, like Astrid thinking Hiccup is spending too much time with a new dragon rider. A third idea is a time - travel plot where they go back in time and have to change something in Berk's history to save the future.