One idea could be that Naruto discovers an ancient set of metal armor that has special powers. Maybe it can enhance his chakra control or give him new jutsu. For example, the armor could have the ability to absorb and redirect enemy attacks. Another plot could involve Naruto having to find the missing pieces of the metal armor scattered across different hidden villages. This would lead him on an adventure and force him to interact with different characters in new ways.
Well, the plot could revolve around Naruto being given the metal armor as a gift from a mysterious figure. However, the armor is cursed. Naruto has to figure out how to break the curse while still using the armor's power to fight against a new threat to the village. He might have to seek help from old enemies who have knowledge about the origin of the armor and how to deal with such curses.
A possible plot is that the metal armor was created by an ancient Uzumaki clan member. Naruto finds it and has to learn how to unlock its full potential. The armor might also have a mind of its own and initially resist Naruto. As he tries to bond with it, he discovers secrets about his own clan. Also, an enemy could be after the armor, which would create a lot of action and conflict as Naruto has to protect it while also learning to use it.
One idea could be that Naruto discovers a pair of ancient metal claws with special powers. For example, they might enhance his physical attacks and also allow him to climb walls like a ninja from the Hidden Stone Village. He could then use these claws in battles against new and powerful enemies, such as a group of rogue ninjas who are after the secret of the claws.
One idea could be an armor that enhances Naruto's Rasengan. For example, it has special chakra - conducting materials that allow him to charge the Rasengan faster and with more power. Another idea is an armor that can change its form according to different battle situations, like becoming lighter for speed - based attacks or heavier for defense when facing strong opponents.
One idea could be Naruto discovers an ancient scroll that details the secrets of the black lightning armor and he has to train in isolation to master it. This could lead to him developing new techniques related to the armor.
Perhaps a story where some of the Metal Gear technology finds its way into the Naruto world. Orochimaru might be interested in getting his hands on such advanced tech for his experiments. He could try to reverse - engineer it to enhance his own abilities or create new, powerful jutsu. And Konoha would have to deal with the threat of this new, unknown technology while also facing their regular enemies.
One idea could be a story where Queen Chrysalis, instead of her usual villainous ways, is forced to team up with Shining Armor for a common goal. Maybe there's a greater threat to Equestria that they both realize they can't handle alone. This could lead to an interesting dynamic as they learn to trust each other.
One idea could be to have Naruto characters infiltrate a Metal Gear - like facility. For example, Naruto's shadow clones could be used to distract the guards while Sasuke tries to find and disable the main weapon system, similar to how Solid Snake would operate in the Metal Gear Solid games.
One idea could be a crossover with a post - apocalyptic zombie world. The Twisted Metal drivers have to not only compete against each other but also fend off hordes of zombies. For example, Sweet Tooth could use his ice cream truck to mow down zombies while also trying to outmaneuver other competitors.
One idea could be an OC who is a master of stealth technology, perhaps even surpassing Snake in some ways. They could be on a mission to uncover a new type of Metal Gear that has been secretly developed by a rogue faction within the military - industrial complex. Another plot could involve an OC who has a unique connection to the AI systems in the Metal Gear universe, and they have to prevent the AI from going rogue and causing global chaos.
A great plot idea for Twisted Metal Black fanfiction would be a time - travel story. A character could go back in time to prevent a certain event that led to the creation of the Twisted Metal tournament as we know it. This would change the entire landscape of the game's world. They might meet younger versions of the existing characters and have to convince them of the impending doom if things don't change.
One idea could be that Amy initially sees Metal Sonic as a threat but then realizes he has some sort of glitched 'conscience' and tries to help him. For example, she might notice that he is being controlled against his will in a way and tries to free him from that control.