Jjaro

The Jjaro are a fictional, extremely mysterious and ultra-advanced extraterrestrial race in the Marathon Trilogy and in Pathways Into Darkness (both by Bungie Software). Almost nothing conclusive is known about them and a lot information about them is contradictory. The Jjaro have been said to have left the Milky Way galaxy if not the universe millions of years ago, leaving behind strange technological/magical artifacts on many worlds. They are first introduced in Pathways Into Darkness in 1994, in which they warn Earth of the imminent threat of a "waking god" (possibly a W'rkncacnter, a chaotic entity from the Marathon universe). They never appear in gameplay, and in the Marathon Trilogy are referred to only within the computer terminals.

It is likely that the character Yrro in the mythology of the S'pht was either a member or collective representation of the Jjaro. The Jjaro are opposed to the W'rkncacnter and it is suggested that they may be of the same origin. The AI Durandal is obsessed with discovering the secrets of the Jjaro and believes they possess the knowledge of how to escape the universe and thus become God-like.