Well, such could very interesting, however writing takes time and lots of it.
Description, scene, and characterization are very essential to making a story come to life.
Usually a rhetorical purpose to drive the story for the audience is important as well.
Even an ill ending one with the promise of rebirth from death can have grand rhetorical purpose.
Still you need things for the audience to grasp onto to reach that purpose.
What do these parasite/hoards look like, who are these valiant defenders? What is the context?
How do such events lead to concur?
It is the asking of questions like these that allows you the author to help build a story for the audience to explore and be impacted by.
This short here is an excellent building block to work on and expand into something with wonderful potential.
Good luck.