It could be a rival singer. In the fanfiction, the rival might spread false rumors about Adam Levine's talent, which gets back to him. Adam, being a sensitive person in this story, would get his feelings hurt by such mean - spirited competition.
A new and over - critical music critic in the fanfiction might be the cause. This critic writes a very harsh and unfair review of Adam Levine's latest album. Adam reads it and, being proud of his work, gets deeply hurt by the unkind words.
Maybe it could be about a negative review of his music. For example, a fanfiction might depict Adam Levine reading a scathing review of his new song. He might initially be shocked and then feel deeply hurt as he reflects on the time and effort he put into the song.
A mysterious new enemy that has infiltrated the village could be the cause. This enemy might be on a mission to disrupt the balance in the ninja world and sees Sarada as an obstacle. They could attack her when she is alone or on a solo mission. Their motives could be related to some ancient grudge against her family or the village as a whole.
He could also develop more empathy for others who are going through tough times. Since he has experienced a major setback, he might be more understanding and willing to help those in need. This could lead to him getting involved in more charity work or mentoring young musicians.
Maybe it was an accident caused by one of his own team members. For example, if Chase was working on a new invention and there was an unforeseen error that affected Adam when he was nearby. It wasn't intentional, but it still led to Adam getting hurt.
Maybe the fanfiction portrays him in a negative light, like making him out to be a bad person or having him do things that are completely against his real - life values.
There are also the possibility of some inter - dimensional beings. In the Ben 10 universe, there are many different dimensions. If a being from another dimension comes through with the intention of causing chaos, they could target Ben. They might have powers that are completely foreign to Ben and his allies, making it difficult for him to defend against them. And let's not forget about the possibility of some of Ben's old enemies teaming up. If they work together, they could come up with a plan to really hurt Ben, whether it's physically or by ruining his reputation among the people he protects.
There could be a new character in the fanfiction, like a bully who targets Lincoln just because he seems like an easy target and ends up hurting him.
It could be a new villain that has emerged. This villain might have some sort of vendetta against Steven specifically, perhaps because of his unique powers or his role in the gem world.
Perhaps it's a mysterious figure in the fanfiction world. This unknown character could have some ulterior motives against Jacob and find ways to hurt him, like setting traps for him.
It could also be a new, unknown enemy. Maybe there's a secret organization that emerges in the fanfiction that has a vendetta against those with electric powers like Michael. They could target him specifically and cause him harm.