The Great Andromeda Invasion
Very important event in my world, isn't really fleshed out yet. Feel free to ask questions.
The Milky Way Galaxy had been invaded by the Andromeda Galaxy. Whilst the Milky Way is made up of a bunch of different aliens, the Andromeda had been colonized completely by one alien species that completely gave up their organic forms and uploaded themselves into hyper-efficient robot ones. They got rid of all the emotions they felt they "didn't need", including pain and feel themselves to be superior because of so. That, along with their arrogance, is their main weakness.
In the territory (now referring to it as the "protag-territory") my world takes place, the Andromeda aliens had taken some territory right next to it, and had gotten the attention of all the natives living in the protag-territory, and started fighting back against them. An alien nation from outside the territory moved their military and set up base in the protag-territory, and did so because they wanted to fight the Andromeda aliens. These alien had completely embraced organic life, and everything about them was either bred or grown, even their ships were completely organic and alive. They definitely did not like that the Andromeda aliens had given up their own bodies for the sake of being the "superior" species. However, as you can imagine, having organic warships with vulnerable insides introduces a lot of problems, as well as having everything else be organic as well.
Meanwhile, there is this species native to the protag-territory that is kind of in the middle. They have a really complicated backstory I'm not going to share here but basically they were engineered, and naturally use a metal element called Philranium that is present in many places in their body, including their armor. They also have a lot of traits that would be impossible to evolve naturally, especially regarding their brains. They rely a lot on companion animals, because a lot of the companion animals are their ships. They are not nearly as vulnerable as the organic alien species' ships are, in fact 80% of their body is considered the "ship" part. These aliens' weaknesses are pretty balanced, and they have the most unique and powerful military in the protag-territory. Most importantly, however, they have a keen understanding of themselves and the creatures they use because they didn't rush themselves into a life they merely thought would help them, and didn't force it despite all the problems it causes just for the sake of being their idea of "superior".
These aliens are also fighting back against the Andromeda aliens' war of conquest, at first they work with the organic aliens but then stop liking them once they start breaking laws and damaging the environment around them just so they could fight the Andromeda aliens.