The Traveler



The Traveler is a mysterious sphere floating above Earth. Massive in scale, it is unknown whether the huge celestial object is simply a derelict spacecraft or a sentient being in itself. Hanging motionless in the skies above the last human city built in its shadow, it protects the humans from the continuous onslaught of various alien races bent on humanity's eradication by projecting a shield around the City, and gifts the Guardians with ancient and mysterious powers.

History
When the Traveler first arrived to the solar system, it first visited Jupiter, Mercury and Venus, drawing humanity's attention. By the time Ares One landed on Mars, the Traveler had brought the first rain to the desert planet. It helped humanity expand across the solar system, teaching humans new technologies, helping them terraform planets and leading humanity into a Golden Age. Some time later, the Traveler's main enemy, the Darkness, battled with the Traveler, leading to the destruction of almost all human civilization in an event known as the Collapse. At the end of the wars that terminated the Golden Age, the Traveler, in its sacrificial last gift to humanity, came to rest over a small area of the now wasted human planet. As humanity struggled to rebuild itself from these events, the crippled object gifted its protection and powers to the recovering humans. Although the times after the war were difficult, humanity persevered and with the help of this celestial guardian, the humans eventually began to re-explore their terrestrial and solar domain. In its last breath, the Traveler created the Ghosts, to seek out those who can wield its light as a weapon. The Ghosts revived fallen warriors as Guardians, protecting humanity when the Traveler no longer could.

The remnants of humanity built the City beneath the resting place of the Traveler, where they were safe from the continuous onslaught of various alien races such as the Cabal and the Fallen. This city rests in the shade of the great sphere, built under its protective aura as a last bastion of humanity. The Guardians are destined to protect this city and its inhabitants, and as such are gifted with some of the magnificent powers of the Traveler. Some believe that the Traveler chose Earth for a reason, and it is humanity's obligation to prove itself worthy of its light.

With the Darkness returning, humanity fears they will not be able to survive it this time. As a last ditch effort, the player is given the ultimate task of attempting to wake the Traveler before the Darkness arrives, in order to drive it back. The Guardians are able to help the Traveler slowly restore its light, first by stopping a Hive ritual in the Chamber of Night that is siphoning light from the Traveler, and then destroying the heart of the Black Garden.

Trivia

 * The Traveler first appeared in another Bungie game, Halo 3: ODST, where a hidden poster made it appear innocuously like the Moon.
 * The size of The Traveler has changed on numerous occasions in artwork, sometimes being the size of a moon, to being the size as The City.
 * According to Xûr, there is a dark mirror of the Traveler.

List of appearances

 * ''Law of the Jungle
 * Destiny