A plot could involve a trainer from Pokemon Gold finding a rare Pokemon in the Ruby region that has a special ability. This discovery leads to a race among other trainers to either protect the Pokemon or use it for their own gain. The trainer from Gold has to use his knowledge and skills from his own region to keep the Pokemon safe.
One idea could be a story where the characters from Pokemon Gold and Pokemon Ruby team up to stop a new, powerful villain who is trying to control all the Legendary Pokemon. They could travel through both regions, facing different challenges along the way.
One idea could be exploring an alternate timeline where the main character makes different choices. For example, choosing a different starter Pokemon and how that changes their entire journey. Another could be focusing on the backstories of the Gym Leaders in the Pokemon Gold game, like what led them to become Gym Leaders.
A really interesting plot for a Pokemon Ruby and Sapphire fanfiction could be set in an alternate Hoenn region. In this version, the roles of certain Pokemon types are reversed. For example, Water - type Pokemon are rare and Electric - type Pokemon are the dominant force in water - based areas. The main character could be a trainer who has to adapt to these new rules. They might have to find creative ways to battle and train their Pokemon. This could lead to some really unique and exciting adventures, as they encounter different challenges and make new friends and enemies along the way.
One idea could be exploring an alternate timeline where the main character makes different choices in the game. For example, choosing a different starter Pokemon and how that changes their entire journey through the Johto region.
One idea could be a crossover between the two generations. For example, a trainer from the Red era travels to the Gold region and has to adapt to the new Pokemon and different gym challenges there. Another could be exploring the backstories of some of the less - known Pokemon in both games. Maybe there's a hidden mystery about a certain Pokemon's evolution that a fanfiction could uncover.
One idea could be a story about a trainer who discovers a rare and powerful Pokemon in the Johto region that is not typically found in the games. For example, a shiny, alpha form of a Pokemon like Totodile. The trainer then has to protect this Pokemon from a mysterious organization that wants to use it for evil purposes.
One idea could be exploring an alternate version of the Gold story where the protagonist teams up with a rare and powerful Pokemon from the start. This would change the power dynamics and how he faces challenges.
One idea could be to focus on a new trainer in the Ruby Scar region who discovers a rare and powerful Pokemon that has been lost for centuries. This Pokemon could hold the key to an ancient mystery that the trainer then sets out to solve.
One idea could be exploring an alternate universe where the starters of Ruby and Sapphire have different evolutions. Another could be a story focused on a side character from the manga, like giving a backstory to a Gym Trainer. Maybe also a story where the legendary Pokemon Groudon and Kyogre form an unexpected alliance instead of their usual rivalry.
One idea could be to focus on a trainer who discovers a rare and powerful Pokemon in an unexpected part of the Hoenn region. Maybe a Pokemon that was thought to be extinct. Another could be a fanfic where the main character has to stop an evil team from misusing a powerful ancient artifact in Ruby's world. Or perhaps a story about a Pokemon trainer who befriends a Pokemon that has trouble evolving and they go on a journey to find a special way to make it evolve.
Well, a cool plot for 'pokemon adventures gold and crystal fanfiction' could be centered around a time - traveling pokemon. This pokemon accidentally sends the main character back in time to when the Johto region was first being settled. The character then has to figure out how to get back while also dealing with the primitive pokemon training methods and different cultural views of pokemon. Or perhaps a plot where a powerful but cursed pokemon is found in the Crystal Cave. It curses those who try to catch it with bad luck, and the main character has to find a way to break the curse and catch the pokemon without getting too much bad luck himself. Also, a plot about a secret pokemon league tournament that only the best trainers in Johto are secretly invited to could be really exciting.