There could be an interdimensional being that thrives on chaos. It sees the meeting of Jack Frost and Sonic as an opportunity to cause mayhem in both of their worlds. It starts by creating disasters in both the wintry realm of Jack Frost and the colorful world of Sonic. To stop it, Sonic and Jack Frost must figure out the being's weakness while also trying to protect their respective homes and friends.
Well, it could be that Jack Frost is creating his icy landscapes when Sonic zooms by. Sonic is curious about this new, frosty world and Jack Frost is equally intrigued by Sonic's speed. They might start off a bit wary of each other but then realize they can team up. Maybe there's a common enemy that likes to disrupt both Sonic's green, vibrant world and Jack Frost's wintry domain. So they combine Sonic's speed and Jack Frost's ice powers to defeat this foe.
A powerful ice - demon could be a great antagonist. It could be jealous of Jack Frost's power over winter and Danny's ghost powers, so it tries to take over their powers and rule both their worlds.
Thor might be a great ally for Jack Frost. Thor is used to dealing with magic and powerful beings from different realms. He would be less likely to be intimidated by Jack Frost's powers. They could both use their elemental - related powers (Thor with lightning and Jack Frost with ice) to create powerful combined attacks against their enemies. For example, Thor could strike his lightning into Jack Frost's ice structures, creating a powerful blast of energy.
His parents could be in his family. Maybe his father is an ancient frost giant with great power over ice and snow, and his mother could be a gentle spirit who gives life to the frozen landscapes. There might also be siblings, like a sister who can create beautiful ice flowers.
The main antagonist could be an evil sorcerer who has corrupted the Black Knight and is using him to carry out his dark plans. This sorcerer could be after Sonic's speed power to enhance his own magic.
Yes, there are quite a few out there. You can check some popular fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'jack meets sonic' on their platforms and you'll likely find a variety of stories with different takes on this crossover.
One possible plot could be that Jack and Sonic are brought together by a strange interdimensional rift. They have to work together to close the rift while also facing enemies from both of their worlds that are trying to take advantage of the chaos.
The main characters are obviously Jack Frost and the Guardians. The Guardians typically include characters like North (Santa Claus), Tooth (the Tooth Fairy), Bunny (the Easter Bunny), and Sandy (the Sandman).
In this fanfiction, Elsa and Jack Frost are the main characters. Elsa is a complex character, initially feared in her own kingdom because of her powers. Jack Frost, on the other hand, is a more free - spirited character who loves to play with children and spread winter magic. Their meeting in the fanfiction likely brings out new aspects of their personalities as they interact.
Well, in such a fanfiction, Jack Frost could bring his icy powers to the Avengers. Maybe he'd help them fight against a new villain who has a weakness to cold. He could freeze the bad guy's weapons or create ice barriers for the Avengers to take cover behind.