A Different Type of Front

This is a massive crossover story featuring Call of Duty Infinite Warfare, though will eventually move into a drastically different setting and theme, with significant differences between the original IW setting.
List of stuff incorporated(so far):
Call of Duty Infinite Warfare
Attack on Titan
ATLA
Nihonkoku Shoukan
Demon Slayer
Darling in the Franxx
Gate Anime
Code Geass
Wolfenstein
Various references and inclusions of stuff in:
SCP Universe
COD Advanced Warfare
Detroit Become Human

Why is it that from the ashes, great powers will somehow manage to arise and even rival those who arose with greater means? Why is it that they, through sheer will and spirit, would somehow manage to ascend to greater heights and accomplish feats that even the old races could only dream of?

This story shall answer that question through the eyes of a few soldiers, to that of entire nations and empires, and to untold trillions across the stars and the Galaxy, in which shall begin through a simple anomaly, that shall begin to unravel what humanity was too blind to see due to their own bickering and hubris.

They were destined to reach new frontiers and delve even deeper into the darkest shadows, and as the United Nations Space Alliance slowly heals the scars and wounds from the devastating Settlement Defense War, an exploration fleet heading to a new system shall unknowingly set off a chain of events that will determine the survival of humanity, and their ascension to the status of a Galactic Hyperpower.

(Chapter timelines for this story will eventually delve from days apart to entire years. I plan on crossing over a lot of stuff I can for this story.)
(Disclaimer. I do not own the anime nor the shows, nor COD IW in this fanfic. I also do not own the pictures or youtube videos shown. All of these belong to their respective owners. Also, please know that some chapters may have smut in them, though they will be separate and explicitly outlined if you do not wish to read these parts.)