Perhaps the baby is a key to a truce between Spartacus' rebels and the Romans. Ilithyia, being from a Roman family, could be in a difficult position as she tries to balance her love for the baby and her loyalty to her people. The story could explore how Spartacus and Ilithyia work together to ensure the baby's safety and the future of their people.
Their relationship could develop through their shared love for the baby. At first, they might be at odds, but as they care for the baby together, they start to understand each other better. For example, Spartacus could see a different side of Ilithyia as she shows her maternal instincts.
Yes, there are some really interesting ones. You can find them on various fanfiction websites. Some focus on the forbidden love between them, exploring how their different statuses in society add to the complexity of their relationship.
A crossover with a modern - day action story could be really cool too. Spartacus and his crew could be brought to the present day through some time - travel mishap. They then have to navigate the modern world, learning about new weapons and technology. They could use their ancient fighting techniques in modern combat situations, like taking on a powerful criminal organization.
Fanfiction.net is a great place to start. It has a large collection of fan - created stories, and you might be able to find some good ones about Ilithyia and Spartacus there.
Perhaps a story where the baby malachite is a special kind of malachite that is prophesied to bring great change to its realm. Some might want to protect it while others might see it as a threat. The baby malachite then has to deal with all these different attitudes towards it. It could also be about its relationship with a wise old mentor who teaches it about its heritage and the responsibilities that come with its powers.
One idea could be a story where Baby Nightwing is discovered by the Justice League. They have to figure out how to take care of him while also protecting him from villains who might want to use him. Another could be a time - travel story where an older hero goes back in time and meets Baby Nightwing, and has to ensure his safety so that the future doesn't change.
One idea could be a story where the baby Mikaelson has unique powers that start to manifest at a very young age. Maybe they can communicate with spirits, and this leads to all sorts of adventures as the family tries to protect the baby from those who might want to use their powers.
One plot idea could be that Baby takes over Goku's body and tries to use his power to conquer the universe in a more subtle way. He might pretend to be Goku at first and manipulate his friends into doing his bidding without realizing it.
One idea could be exploring what would happen if Maleficent had a baby with a human. Maybe the baby would have a unique blend of magical and human traits, and the story could follow how the baby is accepted or rejected in both the human and magical worlds.
One idea could be a story where the baby in the 'baby project' has some sort of special power that the characters have to figure out how to manage. Maybe the baby can communicate telepathically and it leads to all sorts of comical and heartwarming situations as the characters try to understand what the baby wants.