I'm a huge Halo nerd, so I couldn't help but play around with this mod.
I'm also a bit of a tinkerer, so I do that as well. Using some parts of the mod, for which all credit goes to testpilot14 and Bungie respectively, I've made a derivative mod. In it, the Graycollars are transferred from being notGermany to notUNSC (namely because I can't figure out how to make new factions

). All default German weapons, alongside the camouflage suit because it isn't used by NPCs by default, have been reskinned and modified into UNSC equipment:
The G36 is now the MA5C Assault Rifle
The Glock 17 is now the M6C/SOCOM Magnum
The IMI Negev is now the M739 SAW
The M2 Carl Gustav is now the M41 SSR MAV/AW
The PSG-90 is now the SRS99C-S2 AM
The Scorpion-EVO is now the M7S SMG
The SPAS-12 is now the M90A CAWS
The Steyr TMP is now the M7 SMG
The Camouflage Suit is now an ODST Recon Suit
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In 2537, the UNSC
Luck's Draw made a slipspace jump towards the Leonis Minoris system acting on orders to reinforce defensive forces with the 61st Marine Regiment. However, due to a slipspace anomaly of unknown cause, upon exiting slipspace the ship found itself in orbit above Earth.
Three months later, it's been determined that they've travelled backwards in time, and are on top of that within another timeline of history. Here, the United States and Russia, upon discovering the Aphresian continent, have engaged in a land grab that UNSC officers on board have decided cannot be allowed for either side.
Now, you are but one of thousands of UNSC Marines running with rifles, engaged in a three-way war between the three greatest powers that Earth has seen thus far. It is your duty to win victory for the side nicknamed Graycollars by both American and Russian forces.