Traveling the universe in search of extra-terrestrial trouble is a time-honored science-fiction tradition, and it is heartily fulfilled in every installment of the Stargate franchise. The eponymous Stargates have transported the original SG-1 team around the galaxy, while they’ve taken the Atlantis team and the crew of The Destiny even further. In all three series, the members of the Stargate program have encountered countless alien species, some helpful, some antagonistic, and some that are happy to be passive bystanders to the chaos.

In Stargate SG-1, the main team spearheaded the first exploratory missions to other planets, setting the stage for other SG teams and Stargate Command to negotiate and trade. Their adventures began because of the Goa’uld, whose habit of enslaving humans launched a galactic war. As a result, Earth was prompted to seek out technology and aid from distant cultures. Humanity’s foray into the Pegasus galaxy revealed more enemies, some even deadlier than the body-snatchers from home. The mission of the spaceship Destiny, meanwhile, was to unearth the history of the universe from humanity’s Ancient ancestors. There was a great deal of interspecies interaction, but which races were the most entertaining to watch?

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The Nox

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Early in the days of SG-1’s interplanetary wandering, they encounter a small gathering of people who call themselves the Nox. The Nox appear as vulnerable, elfin creatures, but their true strength is quickly revealed, making SG-1 hope that they have found a way to beat the Goa’uld.

The Nox possess extremely advanced technology. They are capable of resurrecting the dead, rendering themselves invisible, and building cities in midair. They are generous and protective of SG-1, but they are also firm pacifists, unwilling to fight the Goa’uld or free enslaved humans. As one of the Four Great Races, they have the ability to challenge the System Lords, but they are unwilling to fight in any war – a luxury SG-1 do not have.

The Asgard

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Unlike the Nox, with whom they once shared an alliance, the Asgard are a crucial part of the power balance of the universe. They settled on multiple human-colonized planets in the guise of deities, using their complex technology to protect those that would have otherwise been captured and enslaved by the Goa’uld.

The Asgard set up a peace treaty with the Goa’uld in order to expand the areas under their protection, sectors of the Milky Way galaxy that include Earth. The Asgard are close friends of the Tau’ri (humans), and SG-1 especially, right up until their extinction event in season 10 of Stargate SG-1. Since their initial meeting in season 2, the Asgard and Stargate Command have endeavored to help each other during times of crisis.

The Wraith

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Much like the Goa’uld plagued the Milky Way galaxy, the Wraith are the bullies of the Pegasus galaxy. Vampiric in nature and voraciously hungry at all times, the Wraith spend every season of Stargate Atlantis trying to cull as many worlds as possible. Their social structure echoes that of a beehive, with drones, a queen, and a habit of announcing their arrival with ominously buzzing dart ships.

The Wraith’s expansion throughout the Pegasus galaxy was the reason the Ancients sank Atlantis in the first place, an action that preserves their cultural hub but which leaves hundreds of planets open to Wraith attacks. It’s not until the Atlantis Stargate is reactivated that the Wraith are faced with a true challenge: namely, humans who have already decimated one alien empire in their own galaxy.

The Unas

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Before the Goa’uld were able to hunt for human hosts, they spent thousands of years as parasites of the Unas. SG-1 discover the Unas in season 1, episode 10, “Thor’s Hammer,” which is incidentally the same episode in which they meet a member of the Asgard for the first time.

The Unas are massive in stature, and are widely seen as demonic by the human populations that encounter them. In Stargate SG-1, Daniel Jackson befriends a young Unas, and goes on to help him free his community, who have been captured and enslaved by humans. The Unas endure slavery, forced relocation, assault and murder during this series, and sometimes Stargate Command is to blame. Daniel’s support of their independence makes their story hopeful, instead of dark.

The Tok'ra

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While the Goa’uld were dissecting the galaxy for hosts and territories, an offshoot of their species were building a resistance to their efforts. The Tok’ra in Stargate SG-1 are direct descendants of a rebel System Lord, a Goa’uld that rejected the brutal way of life that defined her people. The Tok’ra (which translated, means ‘against Ra’), accept only willing hosts, and share the host body instead of hogging it.

Living so progressively means that the Tok’ra are constantly on the run, changing their headquarters all the time to escape capture by the Goa’uld. The Tok’ra become integral to the machinations of the Stargate program, providing intelligence and protection to Stargate Command. Jacob Carter, Samantha Carter’s father, even becomes host to a Tok’ra, cementing their role as allies.

The Jaffa

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The race of Teal’c from Stargate SG-1, Jaffa are slaves that have been bred by the Goa’uld to host their larval offspring. The larval symbiont does not take over the host’s body, instead lending it enhanced healing and immune protection. However, an adult Jaffa cannot survive without it for more than a few hours. The Jaffa became embroiled in the galactic war when the tyrant Apophis was first attacked, leading to the rebellion of many Jaffa people.

The Jaffa were proud warriors, and worshiped the Goa’uld before the interference of SG-1 and their allies. The physical deaths of the Goa’uld helped to convince the Jaffa people that they were monsters, not gods, and they were soon freed both physically and spiritually.

The Stargate franchise was built around the inclusion of multitudinous alien species, not just specific allies or enemies. Most episodes feature a new alien people, person, or artifact, taking the audience on expeditions of discovery that characterize the entire show. There are many more alien civilizations that make Stargate great, proving that a portal that leads across the universe is the quickest and easiest way to make friends – or new nightmares.

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