Write a H2O, Mako Mermaids crossover fanfiction.

Maybe a magical item gets lost that is crucial to both the H2O and Mako Mermaids' worlds. It could be a pearl that has the power to keep the balance of the ocean's magic. A young mermaid from H2O and a young mermaid from Mako accidentally cross paths while looking for it. At first, they are suspicious of each other. But as they search together, they start to understand each other's powers better. The H2O mermaid can freeze water to access hidden caves, while the Mako Mermaid can use her singing to call upon sea creatures to help. Eventually, they find the pearl and in the process, they create a friendship that bridges the gap between their two worlds.

Emma from H2O and Mimmi from Mako Mermaids would be an exciting pair. Emma is the smart and organized one in the H2O group. Mimmi is also intelligent but has a more free - spirited nature. They could work together to figure out some mystery in the ocean world. Maybe they find an ancient mermaid artifact and have to use their combined knowledge and skills to unlock its secrets.

The plot could involve a mermaid from Mako getting lost and ending up in the area where the H2O mermaids live. The H2O mermaids would be surprised at first but then help the Mako mermaid find her way back. Along the way, they exchange stories about their experiences as mermaids, like how they got their powers and what they do to keep their identities secret. And in the end, they form an alliance of sorts.

In this fanfiction, the mermaids from H2O could be discovered by the Avengers. Maybe the Avengers are on a mission near the beach where the mermaids live. The mermaids' unique abilities, like controlling water, could be mistaken for a new threat at first. But then they realize they can work together. The mermaids could use their water powers to help the Avengers during a big battle against a water - based villain like Namor. They form an unlikely alliance and learn from each other's worlds.

One possible plot could be that the characters from Mako Mermaids end up in a different magical realm where they meet the mermaids from another story. They could team up to face a common threat, like an evil sea witch who is stealing the magic from all the mermaids. They would have to combine their unique powers, like the moon pool powers from Mako Mermaids and the special singing abilities of the other mermaids, to defeat the witch.

First, you need to create a well - developed OC. Think about their personality, backstory, and what makes them unique. For example, they could be a human with a special connection to the sea. Then, focus on how they meet Zac. It could be a chance encounter at Mako Island. Build their relationship gradually, adding in some conflict and resolution, like differences in their views on protecting the island's secrets.

Well, the mermaids could be brought to the surface world due to some sort of magical or scientific accident. And the Avengers, being the protectors of the Earth, would initially be cautious but then realize they can be allies. The mermaids might have some sort of ancient magic that could be used to power up the Avengers' weapons or defenses. Or perhaps there's a common enemy that is after both the mermaids' underwater resources and the Avengers' technology. So they have to team up to stop this greater threat.

Zane would be a great character to include. He has his own charm and knowledge of the human world. If he were in a crossover, he could introduce new technology or ideas to the other mermaids. For example, if he crossed over with mermaids who are more primitive in their ways, he could help them modernize their defenses against threats. And he could also learn a lot from their ancient magic and traditions.

Love and relationships are also popular themes. The h2o characters might fall in love with characters from the other crossover story. This could create interesting relationship dynamics and storylines, like a mermaid falling for a human from a different fictional world.

Hulk and a mermaid with strong physical abilities. The Hulk is all about brute strength on land, and the mermaid could have enhanced strength in the water. Imagine if they had to work together to move a huge object that was blocking a passage underwater or on land. The mermaid could use her fins and water currents to help guide the Hulk's massive strength in the right direction, and the Hulk could protect the mermaid from any threats on land.