One popular theme is alternative universes. Fans like to imagine what would happen if the events of the show took place in a different setting or with different character relationships. For example, Zim being accepted on Earth or Dib being an alien instead.
Some fanfictions also focus on the apocalyptic scenarios in the Invader Zim universe. Given the often dark and strange nature of the show, it's not surprising that fans are interested in exploring what would happen if the world really was invaded by Zim or if some other catastrophic event occurred. These stories can be really intense and action - packed, and they often show different sides of the characters as they face extreme situations.
One popular theme is the relationship between Zim and Dib. Writers often explore their rivalry in different ways, like what would happen if they were forced to work together. Another common theme is the exploration of Zim's alien culture and how it clashes with Earth's. It's interesting to see how different authors handle these cultural differences.
Often, there's a theme of self - discovery. As Female Zim is a different take on the character, she might be on a journey to figure out who she is in this new form. Also, the theme of adaptation is common. Just like in the original where Zim has to adapt to Earth, Female Zim may have her own unique ways of adapting, whether it's to Earth's environment or to the reactions of the other characters around her. And there's also the theme of power. How does being female change Zim's perception and use of power? This is something that many fanfictions like to play with.
Dib is also very popular. His obsession with proving Zim is an alien and his determination, despite being constantly ridiculed, give him a lot of depth. Fanfiction often explores his relationship with his sister and his father in more detail, adding to his character.
A prevalent theme in 'Invader Zim baby fanfiction' is the idea of growth and change. Even as a baby, Zim might still have his grand plans of conquering Earth, but he has to adapt his methods. There's also often a theme of protection. Characters like Dib might see the baby Zim as an even greater threat and try to protect the world from him, or in some cases, protect the baby Zim from other threats in the universe.
One common theme is the struggle for power. Zim, as a vampire, often tries to gain more power, whether it's over Dib or in the vampire world itself. Another theme is identity. Zim has to figure out who he is now that he's a vampire. Is he still the same invader or has he changed?
One common theme is the clash of cultures. Naruto's world of ninjas with its honor and traditions is very different from Zim's world of aliens and wacky technology. So, stories often play with how these two different cultures interact.
One popular Invader Zim human fanfiction might be those that explore Dib's life as a human dealing with Zim's alien antics in a more in - depth way, like how he tries to convince the world of Zim's true identity while also facing normal human problems. Another could be stories that focus on Gaz's relationships with other humans in the context of the strange happenings in town because of Zim.
You can try fanfiction websites like FanFiction.net or Archive of Our Own. There are often a lot of fan-written stories about 'Invader Zim' on these platforms. Just search for 'Invader Zim' in the search bar and you'll be presented with a variety of fanfictions.
Another theme is the relationship between Dib and Zim. In many fanfictions, their rivalry either intensifies or takes on a new form. It could be that they have to team up against a new threat that emerged because of the Florpus.
One common theme is the idea of unlikely pairs falling in love. Given the oddball characters in 'Invader Zim', it's often about characters who you wouldn't expect to get together, like Zim and a human. Another theme is the struggle between different species and cultures in the context of love. For example, an Irken and an Earthling trying to understand each other's values while being in love.