Mental and emotional stress also play a big role. Sam has been through so much trauma in the series, and in fanfiction, this can be amplified. If he has a major emotional breakdown, it can physically manifest as a collapse. For instance, if he discovers something really disturbing about his past or future, the shock could be enough to make his legs give out.
One common reason is over - exertion. Sam often pushes himself to the limit when it comes to fighting demons or saving people. His body can't always handle the stress and he collapses. For example, in some fanfics he might use too much of his psychic powers without proper rest, leading to a collapse.
Sometimes it's due to Dean's overprotectiveness. He might think he's doing what's best for Sam but in the process, his actions end up causing harm. For instance, he could keep Sam from a mission that Sam believes is important, and in the struggle, Sam gets hurt.
Dean is almost always going to be in these fanfictions when Sam is gagged. Their relationship is central to Supernatural. Rowena could also be a character. She might use her magic to either gag Sam for her own purposes or to help him if she has a change of heart. And Gabriel. He could turn up and use his trickster abilities to either put Sam in the gagged situation as a joke or to get him out of a more serious one.
One common theme is the unrequited love. Often Becky has strong feelings for Sam, but Sam may be oblivious or hesitant. Another theme is Becky trying to fit into Sam's world of hunting and the supernatural. Also, there can be themes of redemption for Becky, as she has made some not - so - great choices in the show, and fanfiction can explore her journey to becoming a better person in relation to Sam.
One common theme is trauma and recovery. Since Sam has been abused, these fanfictions often explore how he copes with the emotional and psychological scars. Another theme is family dynamics. How Dean and other family members react to Sam's situation and how they support or sometimes fail to support him.
Another theme is acceptance. This includes both self - acceptance and acceptance from others like Dean or other hunters. It can be a struggle as the Supernatural world might not be as open - minded as we'd like. In some fanfictions, this is a major plot point where Sam has to fight for his relationship to be recognized.
Loneliness can be a theme too. After being betrayed, Sam might isolate himself, feeling that he can't trust anyone anymore. This can lead to him making some rash decisions. And the theme of revenge also pops up sometimes. Sam may seek to get back at those who betrayed him, which can take the story in a whole new direction.
One common theme is the exploration of power. Since Chuck is a powerful being in the Supernatural series, fanfictions often deal with how Sam interacts with Chuck's power and what it means for their relationship.
The theme of self - discovery is also quite prevalent. As they go through various adventures, Sam and Jack learn more about themselves, their powers, and their place in the world. And family is another important theme. Even though they may not be related by blood, they become like family in many of these stories.
One common theme is Sam's struggle with his health. The seizures can be a symbol of his vulnerability in a world full of supernatural threats. Another theme could be the brothers' relationship. Dean's reaction to Sam's seizures and how he tries to protect and care for his brother. Also, there might be themes related to Sam's inner strength as he copes with this new condition while still being involved in hunting supernatural creatures.
One common theme is Sam's struggle with his identity. Being a young hunter in a world full of the supernatural, he's constantly trying to figure out who he is and what his place is. For example, in many fanfics, he battles between his normal self and the part of him that has to be a hunter.