Guardian Custode

Guardians are Forerunner constructs. At some point in 2558, a Guardian would have an encounter with the Swords of Sanghelios, led by the Arbiter Thel 'Vadam and ONI forces led by Jameson Locke.

Description
Guardians are seemingly somewhat variable in appearance. One variant possesses horizontally ovoid-shaped heads and long, phoenix-like wings consisting of multiple segments, presumably held together by hard light bonds. Another variant, witnessed on Sanghelios, possesses a head that is vertically roughly elliptical (reminiscent of a humanoid face), topped with a broad, vaguely conical protrusion, along with shorter wings composed of comparatively fewer segments. Both variants are enormous; with the variant present on Sanghelios appearing to be hundreds of meters in height. One of the variants possesses long, tentacle-like appendages that protrude from the "chin", similar to the tentacles of Gatherers.

Guardians are capable of concealing themselves underground and can produce powerful shockwaves capable of demolishing buildings and destroying Covenant aircraft.

Behind-the-scenes

 * First seen in the Halo Xbox One announcement trailer and later in the bookend cinematics of Halo 2 Anniversary as well as Halo 5: Guardians promotional artwork, there was considerable speculation as to the nature of the constructs prior to the confirmation of them as the titular Guardians in Game Informer's June 2015 issue. When asked about the construct seen in the Halo 5: Guardians key art on Twitter, the game's Creative Director Josh Holmes alluded to the name by replying that "The answer is in plain sight."
 * The Guardians bear some basic similarities to Forerunner war sphinxes, although the Guardians are far larger.

List of appearances

 * Halo 2: Anniversary
 * Halo 5: Guardians