Mass Effect brings together disparate species from across the Milky Way and Andromeda Galaxies in an underdog bid for survival. With two stories now stretching across vast amounts of space and time, the sci-fi video game setting has touched on many sentient races that may well be fleshed out in new titles.
Mysteries abound in the Mass Effect universe, many of them central to overcoming ancient horrors and preserving the future. Most of these unsolved riddles involve races known only through a few tales and legends preserved by the game’s core civilizations. As players discover more about the setting and lore of the series, new species shall likely continue to come to light and become a part of the growing universe.
The Oravores and Densorin
One of the biggest discoveries the Prothean Javik brings to the Asari with Mass Effect 3’s From Ashes DLC is that it was his race who saved the Asari from the Oravores. Previous Asari teachings asserted that the goddess Athame fought off the dangerous Milky Way race during the previous cycle. The skies lit with fire and the battle against the Oravores became a major part of Asari religious and historical traditions. Javik notes the similarities in appearance between himself and Athame as well as describing the armaments used in the battle over Thessia, homeworld of the Asari, as proof of his recollection of the tale.
Another race from the Prothean era, the Densorin are known best for their mastery of celestial mechanics and interstellar language development. A close second trivia tidbit is the archived fact that they attempted to appease the Reapers by sacrificing an entire generation of their offspring, but to no avail. They also battled the Oravores before the beginning of the Reaper harvest before finally succumbing to the Reapers themselves. Games taking place in Mass Effect’s past may well include at least further tales of the tragic Densorin.
Inusannon and Thoi’han
The Inusannon and Thoi’han fought a massive war tens of thousands of years before Prothean culture came to prominence. In the ruins of the giant ships that saw use in those battles, Prothean excavators found the remnants of mass effect drives and other technology that would come to define the era. Broken machines and destroyed Inusannon devices found on Eingana and Ilos also corrupted the surrounding landscape with leaked Element Zero, the substance that enables mass effect drives. Both races fell to the Reapers.
Zha’til
The Zha’til were originally the Zha, a spacefaring race that implanted themselves with AI technology in a bid for faster and greater evolution. These cybernetic-style implants were easy prey for the Reapers, who used technology similar to that of the Collectors to transform the species fully into a synthetic slave race. The enslaved Zha’til multiplied quickly, becoming swarms of Reaper servants that descended on and wiped out other civilizations. The Zha’til were themselves destroyed entirely by the Protheans, who triggered a supernova of the star in their home system to eliminate the synthetic threat.
Raloi
The Raloi are one of the few rarely mentioned races that have a solid physical description, being bipedal and bird-like, roughly the size of a human. The race existed in the time of Commander Shepard, and they fled into hiding at the advance of the Reapers.
The Raloi initially encountered the Elcor before being admitted to Council space by the Asari. By destroying all signs of technology around their planet, they hoped to appear as far less technologically advanced than the other races and thus avoid the harvest of the Cycle. The Raloi have no colonies and were isolationist even before the revelation of the Reapers, making them a mysterious Mass Effect race worth exploring in the future.
Kirik
The Kirik are an insectoid species that exhibited signs of sentience and eventually was found to have biotic capabilities. Around 2185 CE, the Citadel Council decided to further examine the Kirik as a candidate for uplifting, a decision that brought with it debate about whether continuing to uplift species was a good idea in the wake of the Rachni Wars and Krogan Rebellions. They may well appear as antagonists in the Milky Way or even merge with the last of the Rachni to become a new species in new Mass Effect titles.
The Jardaan
Future games taking place in the Andromeda Galaxy may well explore the enigmatic builders who are responsible for creating the Remnant AI and Vaults of the region. They also created the Angara, though the reason for completing these impressive feats remains a mystery. The Angara’s genetic memory is likely a key to unlocking the secrets of the Jardaan, but Mass Effect: Andromeda leaves fans without answers.
As Andromeda's Ryder family learns, the Jardaan’s Vaults could dramatically change the nature of planetary landscapes, making them more or less hospitable over a short period of time. The Scourge that derailed the Andromeda expedition also dramatically affected the Vaults, and upcoming titles may well rely heavily on further unearthing the secrets of those Vaults and their builders.
Kett Vassal Races (The Eealen, Sirinde, and Thusali)
At least three vassal races of the Kett exist in Mass Effect lore. These races failed to prevent exaltation, a physical and mental transformation that results in creatures becoming servants of the warlike aliens, though some members (or at least memories) of the separate species exist. The secrets of the Kett are likely to return as a Mass Effect narrative.
The few remaining Eealen represent a population too far gone to be genetically viable, with most of its members having been exalted by the Kett. These few are known to be wandering nomads, seeking and gathering scattered lore. The Sirinde rely on Kett technology to stay alive, having poisoned themselves to prevent exaltation. The Thusali are known only to have once worshiped the Remnant prior to being almost, if not fully, exalted and absorbed into the Kett Empire.
Mass Effect 4 is in development.