Well, it could lead to a major shift in the story's direction. Maybe Tony's friends would react differently and it could change the whole plot dynamic.
Tony would probably be really hurt. He's a human after all, despite being a genius billionaire playboy philanthropist. Birthdays are special, and for his friends to forget would sting.
I'm not sure specifically as there could be many different interpretations in such a fanfiction. It might involve a character named Rito facing a stabbing incident, perhaps in a battle, a crime scene, or a situation of betrayal.
He could also become more defiant. Instead of trying to win back their favor, he might double - down on his actions and beliefs. For instance, if they hate him for his use of a particular technology, he might continue to develop it just to prove them wrong.
Yes, there might be some fanfiction out there with such a plot. Fanfiction platforms often host a wide variety of creative and sometimes out - of - the - box ideas. You can try searching on popular fanfiction websites like Archive of Our Own.
Pepper Potts could be a big help. She knows Tony so well, and she could try to jog his memory by showing him things from their past together, like pictures or mementos. Rhodey could also be there for him. He could tell Tony stories about their military days and how they became friends, which might trigger some memories.
He might be amused. Tony Stark has a big ego and seeing how fans imagine his adventures in fanfictions could be quite entertaining for him. He'd probably chuckle at some of the wilder ideas and might even be flattered by the creativity of his fans.
It could be a rogue angel. There are always some angels in the Supernatural universe who oppose Castiel's ideas or actions, and they might see stabbing him as a way to get rid of him or send a message.
In such fanfiction, characters might show shock. For example, Dean could be horrified when he sees Castiel stabbed, his eyes wide open and his face pale.
Well, in 'naruto gets stabbed fanfiction', it could be that Naruto is exploring a new and dangerous area where he encounters a powerful and hostile ninja. In the heat of the fight, this ninja manages to land a stabbing blow. It might also be that Naruto is weakened due to some prior injury or chakra depletion, making him more vulnerable to being stabbed by a regular enemy. And, there could be a situation where Naruto is under the influence of some sort of genjutsu that impairs his ability to defend himself and thus gets stabbed.