Obviously, Jack Frost is the main character as the story is about his transformation into a dark version of himself. But there could also be other characters from the original Jack Frost lore, such as the Guardians like North, Bunny, and Tooth. They would likely play important roles, either trying to save Jack from his dark path or being forced to oppose him if he becomes too dangerous.
Another plot could involve Jack Frost being lured into the darkness by an external force, like a shadowy entity. This entity might promise him more power and control over his existence. As he succumbs to it, his appearance could change, his eyes turning a deep, cold black, and his ice becoming darker and more dangerous. His personality would shift from the carefree spirit we know to a brooding and vengeful being.
One idea could be that Jack Frost turns into a human to experience the warmth of human emotions. He might find himself in a small town during winter. As a human, he discovers the joy of a hot drink on a cold day, something he never truly understood as a spirit. He could also fall in love with a local girl who is kind - hearted and loves the winter. This newfound love makes him question whether he wants to return to his former state or stay human forever.
One possible aspect of the 'Jack Frost Dark Side' in fanfiction could be his struggle with his powers. He might be tempted to use them for self - gain or revenge. For example, in some fanfictions, he could be frustrated with how humans treat winter and decide to make it harsher than it should be, causing chaos and destruction.
Well, at first, Jack Frost as a human might be very confused. He could be disoriented by all the new sensations and the lack of his ice powers. But as time goes on, he might start to appreciate the simple pleasures of being human, like the warmth of a hug or the taste of hot chocolate.
Well, one possibility is that he could be taken in by a kind family. They might not know who he really is and just think he's an ordinary baby. They would care for him, feed him warm milk, and keep him cozy in a little crib. As he grows up, he might start to show signs of his magical powers, like making little ice crystals form on his crib railing when he's excited or sad.
Another theme is his isolation. As he delves into his dark side, he may push away those who care about him. This isolation can be both a cause and an effect of his darkening. He might feel that no one understands him and his internal struggles, so he further isolates himself, which only makes his dark side stronger.
One common theme is friendship. Despite their differences, they often come to trust and rely on each other. Another is power. How their unique powers interact and complement each other is often explored.
It's possible that his powers would be more erratic. As a baby, he doesn't have the control he has as an adult. So, his ice - making abilities might go off randomly. For example, he could accidentally freeze the water in a nearby pond just by being near it while having a little tantrum. But as he grows and learns about his powers again, he would start to gain more control over them.
One possible plot could be that Jack Frost is corrupted by a dark force. He starts to spread winter not as a fun, playful season but as a harsh, unforgiving one. He might turn against the other Guardians, believing they are holding him back from his true power.