One scenario could be during a training session at Camp Half - Blood. Maybe he's sparring with a new camper who has an unexpected fighting style and accidentally lands a hard blow on Percy. Another is when he's exploring an old, cursed temple. There could be traps that harm him, like poisoned darts that hit his leg. Or he could be in a fight with a mythical creature that has a special power to cause internal damage, like a basilisk's stare which might make his eyes and head hurt terribly.
Percy could get hurt while traveling through the Labyrinth. The ever - changing passages might collapse on him, breaking his bones. He could also encounter a group of unfriendly nymphs who use their magic to create illusions that lead him into dangerous situations, like walking off a cliff. In a more complex plot, a traitor within the demigod community could set him up, leading him into a fight with a much stronger enemy, resulting in severe injuries all over his body.
He might be on a mission to retrieve a powerful artifact. Enemies could ambush him on the way. For example, a group of evil sorcerers could cast a spell that binds his limbs and then physically attack him. His attempts to break free could cause him to injure himself further. Also, if he were to go underwater to a dangerous part of the ocean, like the lair of a sea monster, he could be bitten or stung, causing him great pain and potential long - term damage.
One possible scenario is that Annabeth might lie to Percy about something really important. For instance, she could lie about her whereabouts when she's actually meeting someone who is not a friend to Percy. When Percy discovers the truth, he would feel betrayed and hurt.
Perhaps in a scenario where Percy is about to sacrifice himself for the greater good. Triton, seeing Percy's selfless act, is so moved that he cries. Another situation could be when Percy is being wrongly accused and is facing great danger, and Triton, who knows Percy's true nature, cries out of frustration and worry for him.
One scenario could be that there are some dark forces in the fictional multiverse that consider Harry Potter fanfiction a threat to the 'original order'. Percy Jackson, being a hero, steps in. He might have to fight off some shadowy creatures that are sent to burn or erase all the fanfiction. His demigod skills like superhuman strength and his ability to control water would be very useful in this fight. And his loyalty to the idea of creativity and different interpretations (represented by fanfiction) drives him to protect it.
In some 'Vegeta and Bulma get hurt fanfiction', it could be due to a betrayal. A supposed ally turns on them. Vegeta, being prideful, might not see it coming at first and get seriously injured in the initial attack. Bulma, who is with him, gets caught in the crossfire. She could be hurt while trying to protect their young son, Trunks. This kind of situation would add a lot of drama and emotional turmoil to the story.
He could get a magical shield that can not only block attacks but also absorb the power of the enemy's blows and use it for his own attacks later. For example, if a fire - breathing monster attacks, the shield could absorb the fire energy and Percy could then release it as a counter - attack.
One possible scenario could be that in the fanfiction, some evil organization captures Percy and tries to figure out his powers related to being a demigod. They might subject him to various tests like trying to measure the limits of his ability to control water, or how he can heal from injuries that would be fatal to normal humans. Another could be that they experiment on his connection to the Greek gods, perhaps trying to sever or manipulate it in some way.
One possible scenario could be that Percy has faced so many traumas and losses in his battles against the monsters and gods' schemes that he simply feels exhausted and wants an end. For example, if he loses his close friends like Annabeth in a particularly brutal way, it might push him to the edge.
One scenario could be that Percy has some sort of magic spell cast on him that makes him smaller. Maybe a mischievous god or a powerful enemy uses a spell to shrink him for their own amusement or to gain an advantage in a battle. This would lead to some interesting situations where Annabeth has to protect him in a different way than usual.
One possible scenario could be Percy being betrayed by a primordial who he thought was an ally. Maybe the primordial promised him power to defeat a common enemy but then turned on him at a crucial moment, leaving Percy vulnerable and alone against a greater threat.
One possible scenario could be that Percy sacrifices himself to defeat a powerful enemy. Maybe he uses his powers to hold off a huge monster that is about to destroy Olympus and in the process, he gets fatally injured and dies. Another could be that he is betrayed by someone he trusts, which leads to his death. For example, a demigod who is jealous of Percy's popularity and powers might make a deal with the enemy and set Percy up.