One interesting fanfiction could be about Metal Sonic being reprogrammed by Tails to fight for good. Tails uses his technological skills to rewrite Metal Sonic's code, and they form an unlikely alliance to protect Sonic's world from a new threat.
There might be a fanfiction where Metal Sonic and Tails are both stranded on an unknown island. At first, they are enemies, but as they face challenges together like finding food and shelter, they start to understand each other more and eventually work together to find a way off the island. This could involve Tails trying to repair Metal Sonic's damaged parts in exchange for help in building a raft or something.
One interesting Metal Tails fanfiction could be about him finding a new purpose beyond being a villain. Maybe he teams up with Sonic to save the world from a greater threat. This would show his character development.
I'm not sure about its popularity. It depends on the fan community. Some might find the dark and edgy concept interesting, while others might not like the idea of Tails being killed off in a fan - made story.
The plot might be centered around a power - hungry or misprogrammed Metal Sonic. Tails could be in the middle of working on a project that could potentially stop Dr. Eggman for good. Metal Sonic is sent to stop this from happening by any means necessary, which unfortunately for Tails means death. It could also explore the emotional aftermath among Sonic and his friends, like how Sonic would react to the loss of his dear friend Tails. There might be a revenge plot where Sonic then sets out to destroy Metal Sonic once and for all.
There are fanfictions where Sonic and Tails time - travel. For example, they might go back to the early days of Mobius and meet their predecessors. This can lead to all sorts of interesting scenarios as they try to avoid changing the future while still learning from the past.
Some Sonic Tails fanfiction focuses on their friendship. For instance, a story could be set during a time when Sonic is injured. Tails has to take on more responsibilities and protect Sonic while also trying to find a way to heal him. This kind of story shows the deep bond between the two characters.
In fanfiction, Metal Sonic often interacts with Tails as an adversary. Since Metal Sonic is usually programmed to oppose Sonic, and Tails is Sonic's friend, Metal Sonic sees Tails as an obstacle. For example, he might try to attack Tails to get to Sonic or to stop Tails from helping Sonic in a fight.
In some fanfictions, Tails' death might be a catalyst for the other characters to come together. Maybe Tails dies while protecting the Chaos Emeralds, and this unites Sonic, Knuckles, and Amy to safeguard the emeralds and prevent further chaos. They might then go on to honor Tails' memory in different ways throughout the story.
There are fanfictions where Sonic and Tails time - travel. Maybe they go back to the time when Sonic first got his speed and Tails helps him train even better, changing the course of their future battles against Dr. Eggman. This type of story can explore their relationship in a different timeline.
In some Sonic hugs Tails fanfiction, it could be set during a celebration. After achieving a great victory for their friends and the whole world, Sonic gives Tails a huge, heartfelt hug. This hug not only symbolizes their friendship but also the joy of their success. It can be written in a very emotional and engaging way, with detailed descriptions of their expressions and the atmosphere of the moment.
One interesting story could be about Tails using his mechanical skills to upgrade the Sonic Underground's vehicles. He might create some high - tech gadgets that help them in their adventures against Dr. Robotnik.