Well, if Percy Jackson were turned into a god in fanfiction, he'd probably have incredible new powers. He might be able to control the seas on an even greater scale than before, and perhaps even manipulate other elements related to water like humidity or fog. His relationships would also change. His friends might view him with a new sense of awe and distance, while his enemies would be even more terrified of him. And he'd have to deal with the politics among the gods, which could be really complicated.
In fanfiction, if Percy becomes a god, he'd likely be given a domain. Maybe it would be something related to heroism in addition to his water - based powers. He could start to look different too, perhaps with a more godly glow or more imposing stature. His mortal family would be in a strange situation. His mother might be proud but also a bit intimidated. And Percy would have to figure out how to balance his new divine nature with his old mortal values.
If Percy Jackson is turned into a god in fanfiction, he could gain immortality, which would be a huge change for him. He'd no longer have to worry about aging or dying in battle. His weapon, Riptide, might transform into an even more powerful divine weapon. He would also have access to the godly realms more freely. He could visit Mount Olympus whenever he wanted and have a say in the godly councils. However, he might miss his old life as a demigod, the adventures with his friends, and the sense of being an underdog fighting against the odds.
Chapter 187, "I Really Need an Apology", is the clearest early answer because it turns Wen Jiaojiao's situation into a concrete plot event. The chapter turns that into something concrete by moving from During the competition, she passed by him numerous times, unfazed by...
Chapter 88, "I Call This a Test of Your Will!", is the clearest early answer because it turns Director's situation into a concrete plot event. Early on, She wanted to refuse, but didn't have the courage to do so.. By the end, Let's go," Jiang Li said in a soft voice..
Chapter 150, "Has She Been Cursed?!", is the clearest early answer because it turns Fire Element's situation into a concrete plot event. It opens with Upon hearing the first part of Jiang Li's words, Zhang Cheng...
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Chapter 365, "Are You Sick?", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Jiang Li didn't make a sound, she merely glanced in the direction of...
Chapter 334, "Do you not want to because you look down on me?", is the clearest early answer because it turns Lin Manru's situation into a concrete plot event. The chapter turns that into something concrete by moving from When their family business started to improve, their income became...
Chapter 377, "Master Above, Please Accept Your Disciple's Bow", is the clearest early answer because a shaky connection becomes usable in the plot.
Chapter 175, "He Tampered with the Food", is the clearest early answer because it turns Shu Yan's situation into a concrete plot event. The chapter turns that into something concrete by moving from Wen Jiaojiao's eyes nearly rolled back into her head.
Chapter 352, "Furong Cake", is the clearest early answer because it turns Lin Manru's situation into a concrete plot event.
Chapter 311, "Signed Jiang Yan", is the clearest early answer because it turns Shen Lan's situation into a concrete plot event. The chapter gives readers a real answer by opening on Shen Lan knocked on the door before entering when Jiang Li was...