Bungie: Pathways Out Of Darkness
Earth was eventually devastated an event known only as “the Collapse”. The tale moves around a society that has dropped from its spacefaring, and is in the process of restoring. This society was eventually saved somehow by The Traveller, i.e. that big orb element hanging over the earth. Threatened by extinction, mankind begins to consolidate and avert their own extinction. The player takes on the role of a Guardian of the City and is tasked with investigating the threat before it wipes all traces of mankind from the universe.