A plot could involve a group of hunters who discover that the spearing on a knot is a sign of an upcoming apocalyptic event. They must then race against time to find out what the knot symbolizes in different supernatural lore and prevent the end of the world. They might split up, with some researching in old libraries and others seeking help from reclusive supernatural experts.
One idea could be a story where a character is speared on a knot during a hunt and it unlocks some ancient supernatural power. This power then becomes the key to solving a series of mysterious disappearances in the town.
Give them normal human flaws. For example, if a character is a hunter, make them afraid of something really simple like spiders, even though they face big supernatural threats. This makes them seem more real.
Maybe in the 'dragon knot fanfic', there is a hidden society that protects the dragon knots. A protagonist stumbles upon this society and has to prove themselves worthy to learn about the secrets of the dragon knots and their connection to the dragons.
One plot idea could be Ketch getting involved in a time - travel adventure within the Supernatural universe. He could go back in time and interact with the Winchester brothers at different points in their lives, changing the course of events in unexpected ways.
One plot idea could be that the Winchester brothers have to face a water - dwelling supernatural creature while on a boating trip. Maybe it's a mermaid - like being that lures sailors to their doom, and they have to figure out how to stop it without getting trapped in its watery lair.
One idea could be a character reincarnating as a powerful supernatural being in a different era and having to adapt to new powers and a new world order. For example, a modern - day human reincarnates as a vampire in the Victorian era and has to deal with the strict vampire society rules while also trying to figure out their new vampiric abilities.
One idea could be that Mjolnir has a connection to an ancient supernatural being in the Supernatural universe. For example, it might be the key to sealing away a powerful demon that was once imprisoned by the Norse gods. The Winchester brothers could find out about this connection and have to protect Mjolnir from various creatures who want to use it for their own evil purposes.
Another plot could involve a Pokemon with psychic powers so strong that it can create entire alternate realities. Trainers get trapped in these realities and have to figure out how to escape while also dealing with the strange Pokemon that exist there. This could involve a lot of exploration and mystery-solving.
A fairy Sim could lose their wings in a magical accident. They then have to go on a quest to find the magical ingredients to restore their wings. Along the way, they meet other supernaturals who either help or hinder them. This could involve a lot of exploration of the different supernatural worlds within the Sims 3 Supernatural game.
One idea could be that the 'daddy' figure in the supernatural world has to protect his child from an ancient evil that has awakened. Maybe the child has a special power that the evil wants to use for its own gain.
Well, a cool plot could be that an ancient, powerful entity from the Supernatural world is awakened in Smallville. Clark discovers it while trying to protect the town. He realizes he can't handle it alone and contacts Bobby Singer through some means. Bobby then sends Sam and Dean to help. They initially have a hard time trusting Clark because of his superpowers, but soon realize they need his help. As they battle the entity, they discover it has ties to an old, forgotten lore that involves both the kryptonite on Earth and a powerful demon they once fought. They have to combine their knowledge and powers to defeat it.