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.
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.
Gohan's character often develops by learning to control his Super Saiyan 3 power better. He might start out as a bit reckless with it and then grow more disciplined. For example, he could initially use it to show off but later realize the responsibility that comes with such great power.
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.
Well, if Naruto goes Super Saiyan 3 in a fanfiction, he would likely gain an insane amount of power. His physical abilities would skyrocket. He could move at incredible speeds, and his strength might be enough to shatter mountains. His chakra would probably combine with the Saiyan power in some unique way, creating new and powerful jutsu.
Well, in this fanfiction concept, Naruto going Super Saiyan 4 could also lead to some interesting character dynamics. His friends might be initially shocked and a bit scared of this new form. Naruto would then have to prove that he's still the same person despite this radical transformation. And as for the enemies, they would surely be caught off - guard and have to quickly come up with new strategies to deal with this super - powered Naruto.
Gohan will most likely encounter other Z - fighters like Krillin and Tien. They were all part of the group back then. Also, there's a good chance he'll meet Master Roshi. Roshi was a key figure in Goku's training, so his interaction with Gohan could be really interesting. He might also come across Bulma, who was always involved in the Dragon Ball story, either by accident or because he needs her help with some time - related technology or something.
Gohan could become more of a leader. With the power of Super Saiyan 5, he would be one of the most powerful beings in the universe. Other Z - fighters might look to him for guidance and leadership. This could bring out a more assertive side of his personality. He would need to step up and make tough decisions for the greater good, which would shape his personality in a more authoritative way.
It would likely include epic battles. Gohan in his Super Saiyan 4 form would engage in intense combat against strong adversaries. His power would be on full display, with energy blasts and super - fast movements.
One common plot twist could be Gohan suddenly losing his Super Saiyan 3 powers due to some external force like a new villain's special ability. Another might be Gohan discovering a hidden potential within his Super Saiyan 3 form that allows him to do something extraordinary, like time - travel. And sometimes, a plot twist could involve Gohan's Super Saiyan 3 form being merged with another power source, creating an entirely new and unexpected power - up.