A possible plot for Sonic Black Knight fanfiction is that the world of the Black Knight is invaded by a strange technological force. Sonic has to not only use his sword - fighting abilities but also his speed to figure out how to combat this new threat that seems to be disrupting the natural magic of the land. He could team up with some of the local characters in ways that were not seen before, like forging deeper bonds with Knuckles or Tails in this unique setting.
One idea could be a new character being introduced into the Sonic Black Knight world. This character could be from another dimension and have unique powers. They could initially be seen as a threat but end up teaming with Sonic to fight a greater evil. Another plot could be Sonic losing his sword skills and having to go through a series of challenges to regain them, all while facing off against old enemies with new twists.
One idea could be Sonic having to face a new dark version of himself created by the Black Knight's magic. This dark Sonic could have different powers and a more menacing attitude, making the battles even more intense.
One plot idea could be Lancelot training Sonic in the ways of the knights. Since Lancelot is a skilled knight, he could teach Sonic about honor, chivalry and different combat techniques. This would be interesting as Sonic's fast - paced and impulsive nature would contrast with Lancelot's more traditional and disciplined approach.
One idea could be Sonic having to face a new and more powerful dark version of the Black Knight. This would test his skills and force him to find new ways to use his speed.
One idea could be exploring Sonic's relationships with the other characters in the Black Knight universe in more depth. For example, his interactions with King Arthur and how they might change over time. Another idea is to create an alternate ending to the game's story, where Sonic makes different choices that lead to a completely new outcome. You could also write a fanfiction that delves into Sonic's thoughts and feelings during his adventures in this medieval - inspired world.
A plot could involve Amy Rose being turned into a different form by the magic in the Black Knight's world. Sonic then has to find a way to reverse it. Along the way, they encounter various characters from the Sonic and the Black Knight game, and together they must face a new, powerful enemy that threatens the entire realm.
One idea could be that the Shadow discovers a hidden power within the Black Knight that could change the fate of their world. Maybe the Black Knight has a connection to an ancient magic that only the Shadow can unlock through their unique bond.
A plot might involve Sonic and Merlina having to team up against a new villain who is using the chaos of the Black Knight's world to gain power. They could face many challenges along the way, like magical traps and illusions created by this villain. And as they work together, Sonic starts to understand Merlina's motives better, and she starts to see the value in Sonic's way of handling things.
One possible plot could be Sonic facing a new, more powerful enemy in the Arthurian world. Maybe a dark wizard has emerged who is corrupting the magical elements of the land, and Sonic has to race against time to stop him before the entire realm is plunged into eternal darkness.
One plot idea could be Dark Sonic having to face a new villain that is even more powerful and is threatening to destroy his world. He has to find a way to control his dark powers even more to defeat this foe.
A possible plot for 'sonic meets sonic boom fanfiction' is that a strange rift in the dimensions brings Sonic and his friends from the classic Sonic world into the Sonic Boom world right when they are about to have a big celebration. However, the Sonic Boom characters are initially suspicious of these new arrivals. But as they start to realize that a common enemy is behind the rift, they join forces. Sonic and Sonic Boom Sonic could have a friendly competition to see who can defeat the most badniks during the adventure, which also helps them bond and understand each other's strengths better.