Well, in the 'tmnt mikey gets mutated fanfiction', it's possible that his mutation changes his appearance in a really strange way. He could end up with extra limbs or some really cool looking scales. His relationships with his brothers might also be affected. For example, they might have to learn to adapt to his new form and abilities, which could lead to some interesting conflicts and heart - warming reconciliations.
In the 'tmnt mikey gets mutated fanfiction', one interesting scenario could be that his mutation is not just physical but also mental. He might start having strange dreams or visions that lead him to discover hidden secrets about their origin or the city they protect. His new mutated state could attract new enemies who are either afraid of his power or want to use it for their own evil purposes. His brothers would then have to rally around him to protect him and the city, leading to a series of intense battles and adventures.
In this fanfiction, Mikey might gain new and unexpected powers. Maybe he could develop the ability to control certain elements like water or fire, which would add a whole new dynamic to his character and the story.