They could go on an adventure to save a shared realm. Maybe there is a third world that is being corrupted by a new, unknown force. Elsa's ice powers and Pitch Black's control over nightmares could be combined in an unexpected way to fight this new threat. For example, Elsa could freeze the physical manifestations of the nightmares while Pitch Black could use his knowledge of the dark to find the source of the corruption.
They could embark on an adventure to understand each other's powers better. Pitch Black has always been associated with darkness and fear, while Elsa has ice powers related to control and protection. They could travel to different parts of their combined world, testing and learning how their powers interact. This could lead to some interesting situations, like Elsa using her ice to contain Pitch's nightmares or Pitch using his influence to make Elsa's ice creations more menacing for their enemies.
One possible plot could be that Pitch Black, in his search for new ways to spread fear, encounters Elsa. He initially sees her as a powerful being he can manipulate. But as he gets closer to her, he starts to have unexpected feelings. Elsa, on the other hand, is intrigued by this dark figure. Eventually, their relationship develops to a point where they share a kiss, perhaps in a moment of mutual understanding and a break from their usual natures.
They could have an adventure exploring uncharted lands beyond Arendelle. Elsa could use her ice powers to cross difficult terrains like frozen rivers or icy cliffs, while Anna would be the one scouting for food and shelter. Maybe they would discover a new tribe with unique customs and make friends with them.
One way their worlds could collide is through a magical portal. Imagine Elsa, with her ice powers, accidentally creating a portal that leads to the dark and dangerous world of Pitch Black. Pitch, being intrigued by Elsa's powers, might try to manipulate her for his own gain. But Elsa, being strong - willed, would resist and perhaps use her powers to fight back against the darkness he represents.
He could go on ice - climbing adventures with Elsa. Since Tarzan is so good at climbing trees in the jungle, he might adapt well to climbing ice cliffs in Arendelle. And with Anna, he could explore the forests around Arendelle, sharing his knowledge of the wild.
Another theme is the idea of isolation. Elsa has been isolated because of her powers, and Pitch is often seen as an outcast in the world of good. Fanfictions may explore how they deal with their loneliness and whether they can find understanding in each other.
Well, they could embark on a journey to find other tailed beasts and try to form a new kind of bond among them. This would be an adventure full of challenges as some of the tailed beasts might be hostile at first. Naruto and Kyuubi, as brothers, would use their combined strength and Naruto's persuasion skills to make peace with them. Along the way, they would also learn more about each other's capabilities and grow closer as brothers.
They could go on adventures to discover lost magical artifacts. For instance, they might search for an ancient wand rumored to have extraordinary powers. Along the way, they would face various obstacles like traps set by long - dead wizards and magical creatures guarding the artifact.
Well, they might embark on a journey to find a lost magical artifact. Since Emmett is physically powerful and Bella is quite intelligent, they could combine their skills. Emmett could handle any physical threats or obstacles, like fighting off wild animals, while Bella uses her wits to decipher clues leading to the artifact.
They could go on a quest to find a lost magical artifact. Maybe it's a powerful weapon that was hidden long ago to prevent misuse. Percy's skills in water combat and Leo's mechanical genius would be very useful. For example, if they come across a flooded cave where the artifact is hidden, Percy can navigate through the water while Leo figures out how to bypass any mechanical traps.
They could go on an adventure to find a hidden magical artifact that was lost in the Forbidden Forest. Along the way, they'd face all kinds of magical creatures, like the centaurs and thestrals. They might have to use their combined magical skills, Harry's Gryffindor bravery and Draco's Slytherin cunning, to get past the obstacles.