The story: A joint operation between UNSC and Swords of Sanghelios, as part of the ANVIL initiative (hence the name of the map) on a Forerunner structure.
Note the style "classic" Forerunner structure that the old nostalgic that I am so fond !!!
Since this is Sword of Sanghelios, which has a brown-orange as the dominant color instead of the Covenant purple traditionally, I have applied this characteristic color to all Covenant material to reinforce their presence!