It could be another powerful villain from the Dragon Ball universe like Cell. Since Gohan and Frieza are starting to form an unlikely bond, Cell might see this as a threat to his own plans of domination. He could try to break them apart and defeat them both.
One possible plot could be that Gohan discovers an injured alien creature that he decides to keep as a pet. However, Frieza somehow gets wind of this unique pet and wants to take it for his own evil purposes, like using its powers for his galactic domination plans. Gohan then has to protect his new pet from Frieza.
Obviously, Frieza would be a main villain. He is always power - hungry and self - centered. If Gohan has a pet with some special powers, Frieza would want to take it for himself or destroy it out of jealousy.
One idea could be that Frieza, after being resurrected yet again, finds himself in a situation where he has to team up with Gohan. During their time together, they start to understand each other's motives and past traumas. Gohan's kindness and sense of justice gradually influence Frieza in unexpected ways.
Then, introduce some shared experiences. Maybe they get trapped in a strange dimension together. In this new and dangerous place, they have to rely on each other's strengths. Goku's physical power and Frieza's cunning could be the keys to their survival. As they go through these experiences, they start to see each other in a new light and their relationship begins to change.
Golden Frieza in crossover fanfiction often brings a new level of power and intrigue. His golden form is a significant power - up in the original series, and in fanfiction, it can be used to create interesting scenarios. For example, he could be paired with characters from other universes, leading to epic battles or unexpected alliances.
Frieza's victims in the manga included many powerful fighters. For instance, he eliminated Dende. His actions were driven by his cruel and power-hungry nature.
Frieza turning good in fanfiction would be a major game-changer. It might involve a character arc where he realizes the error of his ways and strives to make amends, adding depth and complexity to his persona.
First, give her unique abilities. Maybe she can control a different type of energy than other Frieza race members. Second, give her a complex personality. She could be arrogant like the typical Frieza race, but also have a hidden soft side. For example, she might secretly care about the well - being of a small group of beings on a planet she was supposed to destroy.