A collection of diary entrees by an alicorn marine called Endless midnight.
Once part of the 22nd Equestrian Marines corps with 700 other marines aboard the Suthura, when a Xenomorph outbreak hits the ship and she and what few remaining survivors must abandon ship.
follow this rag tag team of marine's story.

Just an Idea I toyed with a while back and decided to give it a go, enjoy.