Exo

"Ask yourself: what threatened your Golden Age ancestors so much that they constructed the Exos to defend themselves?"

- Card blurb

The Exo are a race of humanoid war machines built long ago for an unknown purpose and fashioned in humanity's image. Many of the City's Exo citizens live and work alongside their organic brethren. But others fight again, re-forged in the Light of the Traveler to serve as Guardians.

Overview
Exos appear unyielding and tireless. Mechanically, they are so advanced that only a Ghost can comprehend their inner workings. In many ways, Exos like to think of themselves as human, or having human minds in machine bodies. Every Exo has a number appended to their name that signifies the number of reboots they have experienced. Reboots apparently not only wipe memories, but cumulatively erode an Exo's ability to retain any memories at all. Not all reboots completely remove past memories, though, especially for Guardians, and some can gain access to these buried memories by purposefully dying or killing themselves.

History
The Exos were built during humanity's Golden Age for a long forgotten struggle, possibly against the Vex, with the purpose of protecting their creators. Rasputin was once involved in their command, a fact that some Exos dimly remember. The conflict itself has long been forgotten and the Exo remain ciphers, even to themselves, for their purpose has been forgotten as well. But there is one clue to their origins; many Exos experience a dream they call Deep Stone Crypt, or the "place where they were born." It is described as "the infamous subroutine which seeded the first Exo consciousness." Cayde-6's memories stretch further, where he recalls being a human before traveling to Europa to become an Exo, as he "came there in flesh and bone. Gave everything to the ice. Started over. Rebooted."

Known Exos

 * Banshee-44 - The Tower Gunsmith.
 * Cayde-6 - The current Hunter Vanguard.
 * Eriana-3 - A female Exo who was a part of Eris Morn's ill-fated fireteam organized to kill Crota, Son of Oryx.
 * Exo Stranger - A mysterious female Exo known for observing Guardians. She is not a Guardian herself and lacks a Ghost.
 * Felwinter - A former Warlord who became an Iron Lord. Felwinter Peak is named after him.
 * Lakshmi-2 - A female Exo who represents the interests of the Future War Cult in the Tower.
 * Lilavati-12 - A brash Exo who refused to "follow the orders of a craven and a sycophant."
 * Saint-14 - A deceased Guardian known for his valiant feats who was beloved by virtually everyone he met.
 * Shiro-4 - A Vanguard Scout, adviser, and friend to Lord Saladin who resides in Felwinter Peak.
 * Taeko-3
 * Tinasha-3 - A Warlock who took the name Ashraven and joined the Iron Wolves. Known for her prowess in the Iron Banner.

Trivia

 * During their presentation at the 2013 Game Developers Conference, Jason Staten and Christopher Barrett revealed the Exo as a playable race and described them as being "sinister, powerful, and tireless war machines".
 * Exos were stated to be emotionless in a preview. Game interactions appear to contradict this.
 * Despite being machines, albeit sentient, Exos are able to eat and drink despite not having stomachs.

List of appearances

 * Destiny
 * The Dark Below
 * ''House of Wolves
 * The Taken King
 * Rise of Iron
 * Destiny 2