The Covenant is a fictional military alliance of alien races who serve as one of the main antagonists in the Halo science fiction series. The Covenant are composed of a variety of diverse species, united under the religious worship of the enigmatic Forerunners and their belief that Forerunner ringworlds known as Halos will provide a path to salvation. After the Covenant leadership – the High Prophets – declare humanity an affront to their gods, the Covenant prosecute a lengthy genocidal campaign against the technologically inferior race.
The Covenant were first introduced in the 2001 video game Halo: Combat Evolved as enemies hunting the player character, a human supersoldier known as Master Chief. Not realizing the Halos were meant as weapons of destruction rather than salvation, the Covenant attempt to activate the rings on three separate occasions throughout the series, inadvertently releasing a virulent parasite known as the Flood in the process.
To develop a distinctive look for the various races of the Covenant, Bungie artists drew inspiration from reptilian, ursine, and avian characteristics. A Covenant design scheme of purples and reflective surfaces was made to separate the aliens from human architecture.