Travelling to the original MW2 'verse, Valkyrie and Reaper slaughter all of Shadow Company with the intent of capturing Shepherd before he can unleash his betrayal.
Showing no mercy, they massacre all of Shadow Company, who are no match for them. Destroying multiple vehicles, including M1 Abram tanks, Blackhawks, little birds, Strykers and Humvees, they even shoot down a AC-130 Spectre gunship and a pave low.
They butcher Shadow, with everything at the their disposal, vaporizing, electrocuting, immolating, blowing up, eviscerating, and dismembering all the troops, leaving no survivors.
When done they move off to capture Shepherd.