Xcom AU Idea

So had this thought for an Xcom Au, set straight after the end of the most recent game. Probably in the form of both a timeline with story parts in the more interesting times.

The general idea is an Xcom AU where the poor saps are situated in THE most dangerous universe I can come up with. My initial plan was to simply put every single nasty alien race I could in (Tyranids, Zerg, Covenant, Necrons, Wraith ect.) along with a sprinkling of other nicer ones. Now I was wondering whether it would be better to simply use the base idea of these races to create OC versions rather than adapt their back story to fit them in?

The Galaxy itself would consist of these monsters roaming around wiping out all they can often clashing against each other. A scattering of more powerful races that are able to hold out single handed. Mabe one or two groups of aliens banded together in an alliance (Mass Effect). But generally new races do not last very long once they reach a certain technological point. The Xcom aliens for example are simply attempting to eliminate potential competition.

Its very rough idea so this more of an outline and was after some feedback.


Well-Known Member
Megacrossovers tend to be rather poor read for a few reasons.

  1. Some of the crosses may be unknown to the reader, they are rarely introduced properly and the reader may not appreciate the crosses as you do.
  2. There are too many elements (characters, objects, technologies, plots), giving author fatigue in writing and keeping track of them or reader fatigue for reading and keeping track of them.
  3. And because there are too many elements, usually none of them get properly worked on or only a few elements get focused on while leaving the rest out. Why write a megacrossover when you're focusing only on a few of them?
  4. A lot of them read like checklists and have very little depth.

And as it is, it is not even a proper outline. You're just throwing in all sorts of random ingredients and haven't given a thought of what you want to create from them. See the above point 4.