In a crossover with the Harry Potter universe, Voldemort could be an antagonist. His magic and his army of Death Eaters would be a threat. Gohan's Godlike abilities, which are more physical and energy - based, would be a strange and new thing in the wizarding world. He would have to use his powers to stop Voldemort from taking over Hogwarts and the entire wizarding world.
If it's a crossover with the One Piece world, Blackbeard could be a potential bad guy. His ability to steal Devil Fruit powers and his ambition to become Pirate King could lead to a clash with Gohan. Gohan's pure - hearted nature would be in opposition to Blackbeard's more devious ways, and their battle could be epic, with Gohan's ki powers against Blackbeard's dark powers.
One potential antagonist could be an ancient evil that is awakened by Ichigo's newfound power. This entity might see Ichigo as a threat or as a means to achieve its own dark goals.
The Khaos Brigade could be a major antagonist. Their goal of causing chaos would put them at odds with Gohan's sense of justice.
In a crossover with the DC Universe, Darkseid would be a great antagonist. His immense power and his desire for universal domination would put him at odds with Ultimate Gohan who stands for justice and protecting the innocent.
In a crossover with the 'Star Trek' universe, the Borg could be great antagonists for a godlike Saiyan. The Borg's collective intelligence and adaptability would pose a serious challenge to the Saiyan's power. Another option could be the Daleks from 'Doctor Who'. Their single - minded determination to destroy all non - Dalek life forms would put them at odds with the Saiyan.
Maybe Naruto from Naruto could be a crossover character. His ninja skills and Ichigo's combat abilities could create some unique fight scenes. Also, their different ideologies about friendship and power could lead to some great character interactions.
Perhaps Orochimaru could still be an antagonist. In this fanfiction, he might be jealous of Naruto's new god - like gaming powers and try to steal them for his own experiments.
One potential character could be Naruto from the Naruto series. His ninja skills and strong will could create an interesting dynamic with 'godlike gon'. Another could be Goku from Dragon Ball. The comparison of their power levels and fighting styles would be really cool. Also, maybe Light Yagami from Death Note. The clash between 'godlike gon's sense of justice and Light's more morally ambiguous actions would make for an exciting story.
In a crossover with the Avengers, Iron Man could be an ally. His high - tech gadgets combined with Gohan's power would be a great team. Also in the Pokémon world, Ash could be an ally. Ash's knowledge of Pokémon and Gohan's combat skills could be useful. In the Bleach universe, Ichigo could be a strong ally for Gohan, with their combined sword - fighting and energy - blasting abilities.
One potential crossover character could be Goku from Dragon Ball. Since Naruto has godlike powers in this scenario, a meeting with Goku, who also has superhuman strength and abilities, would be very interesting. They could have a friendly sparring match or team up against a common enemy.
In a crossover with the Bleach universe, Orihime could be part of Gohan's harem. Her kind and gentle nature might be attracted to Gohan's heroism. Rukia, with her strong will and sense of justice, could also find herself drawn to Gohan's similar qualities.