Traveler (Earth-2130)

"They called it the Traveler. We watch as it hangs above. The mysterious sphere, silently protecting us."

- - Cortana

The Traveler is an entity surrounded by mystery who floats above Sera, hanging motionless in the skies of the Ephyra. The Traveler protects humanity on the planet through the rebuilding attempts following the First Contact War through the projection of an energy shield around the city.

History
The origins of the Traveler are completely shrouded in mystery, however, the little that is known can be found in the poem known as Dreams of Alpha Lupi, where it is recognized it was built by the orokin as a means to advance the civilizations they were able to save from the necromorphs at the Ark.

The Traveler's seeming purpose is to aid worlds, although it never made its presence known more than necessary to cultivate cultures and civilizations. Once its work was done, the Traveler would go to the next world without warning.

Saint-14 theorized that the Traveler visited other races' worlds before arriving on Sera and meeting humanity. Both the san'shyuum and the eliksni, before the Whirlwind, once found the Traveler, naming it the "First Oracle" and the "Great Machine", respectively. Additionally, the san'shyuum worshiped the Traveler as an emissary for their gods, which they saw as the orokin, leading to the War of Wills. Following the destruction of the eliksni's homeworld, they started a quest to find the Traveler, leading them to New Eden, which would instigate a large-scale conflict against humanity for the Traveler, one that would guarantee the survival of their own race.

Other races found by the Traveler included the sangheili and asari, propelling them to Tier 2 civilizations, as well as the extinct ammonites. Others such as the banu, and the yahg became aware of the Traveler's existence through orokin technology left behind on planets. The yahg warlord Dominus Ghaul wished to gain the power of the orokin, believing him to be worthy of ascension.