It could be a rogue Saiyan from a forgotten part of the Saiyan history. This Saiyan might have a grudge against the Z - fighters and their descendants, like Pan. He could have developed his own version of the Super Saiyan 4 power in a more evil way and wants to prove his superiority by defeating Pan.
Maybe an alien race that has studied the Saiyan's Super Saiyan 4 transformation and has created a device to mimic and enhance its power. Their leader becomes the main antagonist, seeing Earth as a prime target for conquest. Pan, with her potential to become Super Saiyan 4, stands in their way and has to face this powerful threat.
A dark wizard - like character could be the main antagonist. He has the ability to corrupt the Super Saiyan 4 power and tries to turn Pan into his minion. When Pan resists, he decides to destroy her and everything she holds dear. This would create a high - stakes conflict for Pan to overcome in the fanfiction.
One aspect of Dragon Ball Z Pan Super Saiyan fanfiction could be exploring new power - ups for Pan. Maybe she discovers a unique way to achieve the Super Saiyan form that's different from the traditional methods. It could involve her training in a secret place or having a special encounter that unlocks this power.
Super 17 himself could be the main antagonist if the fanfiction focuses on his corruption. He could be consumed by power and decide to rule over the universe. His already - formidable powers would make him a terrifying opponent for the Z - fighters, and they would have to find new ways to stop him without relying too much on their usual techniques.
A common theme is the growth of Pan. As a Super Saiyan, she would experience personal growth, both in terms of her power and her character. She might learn to control her temper better, which is often associated with the Saiyan transformation.
One idea could be Pan discovers a hidden power within herself that allows her to transform into a unique form related to Super Saiyan 4. Maybe she has to go on a quest to find the knowledge to fully control this power. Another plot could involve Pan traveling to a different dimension where Super Saiyan 4 is the norm and she has to prove herself among stronger Saiyans there.
A fanfiction could explore Pan's journey as a Super Saiyan in Dragon Ball GT in relation to her family heritage. She might struggle with the pressure of living up to the Saiyan legacy. Her Super Saiyan transformation could be a turning point where she finally accepts her role and uses her power to protect those she loves, while also learning about the true meaning of being a Saiyan.
In a fanfiction, Gohan as Super Saiyan 3 could be involved in a time - travel adventure. He travels back to a crucial point in Dragon Ball Z history and has to use his Super Saiyan 3 powers to change certain events. This could lead to a whole new timeline where things are different. For example, he might be able to prevent the destruction of Planet Namek or save some characters who originally died.
One idea could be Gohan in his Super Saiyan 4 form facing a new, powerful enemy from another dimension. He could struggle at first to control the raw power of this form while also trying to protect his friends and family. Maybe this new enemy has the ability to nullify the Saiyan's energy attacks, forcing Gohan to rely more on his martial arts skills that he learned from Piccolo.
It could be Orochimaru. In this fanfiction, Orochimaru might hear rumors about the Dragon Balls and their power to grant wishes. Since he is always seeking power and immortality, he decides to hunt for the Dragon Balls. However, because Naruto is so focused on his own battles against Orochimaru in the ninja world, he fails to realize that Orochimaru's new goal involves the Dragon Balls and the entire Dragon Ball Z universe could be at risk.
A plot could be Gohan using his Super Saiyan 3 form to explore uncharted parts of the universe. He discovers new races and powers, and has to use his form to either protect or learn from them. For example, he might find a race that has a power that can enhance or even rival his Super Saiyan 3 state.
One idea could be Gohan struggling to control the new power of the Super Saiyan God. He might accidentally cause some destruction while training and then have to deal with the guilt and the fear of his power getting out of control.