Arkad - Goa'uld

The Goa'uld are the dominant race in the Milky Way and the primary adversaries from seasons 1 to 8 of Stargate SG-1. They are a parasitic species that resemble finned snakes, which can burrow themselves into a humanoid's neck and wrap around the spinal column. The Goa'uld symbiote then takes control of its host's body and mind, while providing longevity and perfect health. Thousands of years ago, the Goa'uld ruled over Earth, masquerading as gods from ancient mythologies. They transplanted humans throughout the galaxy to serve as slaves and hosts, and they created the Jaffa to serve as incubators for their larvae. The most powerful Goa'uld in the galaxy are collectively known as the System Lords.

Amonet (also spelled Amaunet), played by Vaitiare Bandera (seasons 1–3) – See Sha're.
Anubis, played by David Palffy (seasons 5–7, hooded), Dean Aylesworth and Rik Kiviaho (season 8's "Reckoning"), and George Dzundza (season 8 as "Jim") – A half-ascended Goa'uld System Lord who replaces Apophis as the main enemy in season 5. Based on the god Anubis of Egyptian mythology, the character is first mentioned in season 5's "Between Two Fires" and makes his first appearance in "Revelations". Earth is eventually able to annihilate Anubis's fleet above Antarctica in "Lost City", but Anubis survives in energy form ("Lockdown"). Anubis regains his power throughout season 8 and develops a plan to destroy all life in the galaxy and then repopulate it to his own designs ("Reckoning"). Just as he prepares to use the weapon in "Threads", Oma Desala, who inadvertently aided in his ascension thousands of years ago, engages him in an eternal battle. • David Palffy was cast to play Sokar before he got the part of Anubis. Since Anubis is cloaked all the time, Palffy had to express the character's weight through the voice and movements. Mainly because of the severe time restraints of filming television, the producers gave Palffy no background on the character and encouraged Palffy to experiment and find the character's tone himself. What was under Anubis' cloak became a main question among fandom. Anubis was received as an over-the-top-character, but Palffy pointed to what the character represents, saying "Anubis is a god – he's not fully ascended, he's basically an outcast. And as I say, this resulting displacement of energy that's evil, that has been temporarily harnessed under a hood to give him physical form. He's the image of death, the figure of death incarnate, and he's surrounded by a black robe. That symbol in itself has been around since the dawn of time. That in itself is over the top. His whole existence is basically predicated on living up to that theme, and that's a theme that's time immemorial. And of course, as an actor, you've got to work with that. To do otherwise, to underplay that, will work against the idea of what he represents." Palffy was open to continue playing Anubis beyond season 7, but other actors played the character in season 8.
Apophis, played by Peter Williams (seasons 1–6, 8) – A System Lord and the main villain for most of the first four seasons of Stargate SG-1. Based on the god Apep of Egyptian mythology, the character gained power after Ra's death in the film and commands a raid on Earth and Abydos in "Children of the Gods". His then-First Prime, Teal'c, defects from his army afterwards. Apophis's standing amongst the System Lords is severely diminishes after a failed full-scale assault on Earth in season 2's "The Serpent's Lair". After defeating the Goa'uld Sokar's massive fleet and army in season 3's "The Devil You Know", Apophis becomes the most powerful Goa'uld in the galaxy. Despite his death aboard his Replicator-infested ship in season 5's "Enemies", Apophis appears in visions and alternate universes in season 6's "The Changeling", season 8's "Moebius" and Stargate: Continuum. The astronomers David J. Tholen and Roy A. Tucker enjoyed the character so much that they named a near-Earth asteroid that they co-discovered in 2004, 99942 Apophis.
Ba'al, played by Cliff Simon (seasons 5–10) – A System Lord based on the Baal of Canaanite religion. Introduced in season 5's "Summit" and recurring until the end of the show, he is the longest-running villain in Stargate history. After Anubis' fleet is destroyed in season 7's "Lost City", Ba'al gains substantial power and wages a war against all other System Lords, driving them to the brink of defeat in early and mid-season 8. Anubis' return in "Reckoning"/"Threads" forces Ba'al back into his service. Ba'al secretly collaborates with SG-1 and Jacob/Selmak to thwart Anubis' plan of overtaking the galaxy with the Dakara Superweapon, but flees when the Jaffa storm his mothership. With his traditional power base gone, Ba'al exiles to Earth and takes over the Trust, posing as a wealthy businessman in season 9's "Ex Deus Machina". Having made multiple clones of himself, Ba'al begins a campaign to battle the invading Ori for control of the galaxy in "Stronghold" and tries to gain power through various means in "Off the Grid", and season 10's "Insiders" and "The Quest". Ba'al captures Adria in "Dominion" and implants one of his cloned symbiotes within her, massacring most of his other clones with symbiote poison. The Tok'ra extract the symbiote from the last Ba'al clone in Stargate: Continuum.
Camulus, played by Steve Bacic (season 8) – A System Lord who visits the SGC in season 8's "New Order" to first negotiate a new arrangement against Ba'al only to later request asylum on Earth to hide from Ba'al. Camulus leaves Earth in "Zero Hour" with a ZPM, in an alleged attempt to assassinate Ba'al. Camulus appears briefly in the alternate timeline of Stargate: Continuum as one of Ba'al's lieutenants.
Cronus, played by Ron Halder (seasons 3–4) – A System Lord, named for Cronus in Greek mythology. He was the one who banished Sokar. After Cronus punished Teal'c's father (Cronus's First Prime) with a painful death for losing an unwinnable battle, Teal'c became the First Prime of Apophis, mortal enemy of Cronus, to avenge his father's death. Cronus first appears in season 3's "Fair Game" alongside Nirrti and Yu to negotiate Earth's entry into the Protected Planets Treaty. Cronus is shot dead by an android Teal'c in season 4's "Double Jeopardy". Cronus appears briefly in the alternate timeline of Stargate: Continuum as one of Ba'al's allies.
Hathor, played by Suanne Braun (seasons 1–3) – The Queen of Ra and mother of Heru-ur, whom archaeologists find imprisoned in a sarcophagus in Mexico in season 1's "Hathor". Her breath contains a brainwashing drug that enables her to influence males. After temporarily taking over the male population of the SGC in "Hathor", she creates an elaborate replica of the SGC in "Out of Mind"/"Into the Fire" to trick SG-1 into giving her much-sought information. O'Neill throws her unprotected into a cryogenic chamber, thus killing her.
Heru-ur, played by Douglas H. Arthurs (seasons 2, 4) – A System Lord, named for Horus in Egyptian mythology. He is the son of Ra and Hathor, and is a sworn enemy of Apophis. Heru-ur is introduced in season 2's "Thor's Chariot" as an invader of the planet Cimmeria, but an arriving Asgard mothership forces Heru-ur to retreat. In "Secrets", Heru-ur unsuccessfully tries to seize Amonet and her Harcesis child to fight Apophis. In season 4's "The Serpent's Venom", Heru-ur eventually plans an alliance with Apophis, but after the Tok'ra and SG-1 sabotage their meeting, Apophis destroys Heru-ur's ship and absorbs his forces.
Klorel, played by Alexis Cruz (seasons 1–3) – See Skaara.
Nirrti, played by Jacqueline Samuda (seasons 3, 5–6) – A System Lord interested in engineering an advanced human host (a hok'taur) for herself. Named for Nirṛti in Hindu mythology, she is first mentioned in season 1's "Singularity", where she wiped out a planet's entire population except for one girl she experimented on, Cassandra. Nirrti first appears in person in season 3's "Fair Game" alongside Cronus and Yu to negotiate Earth's entry into the Protected Planets Treaty, and she is handed over to Cronus after attempting to murder him. After Cronus' death in season 4's "Double Jeopardy", Nirrti appears in season 5's "Rite of Passage" when Cassandra's modified DNA causes life-threatening physiological changes. In season 6's "Metamorphosis", Nirrti conducts experiments on the local population (and later SG-1) using an Ancient DNA resequencer. A local eventually rises up and kills her by telekinetically breaking her neck. Nirrti appears briefly in the alternate timeline of Stargate: Continuum as one of Ba'al's lieutenants. • Jacqueline Samuda played the part as if "Nirrti always has a secret, something up her sleeve that no one else knows, and that's always playing in the subtext. That way she always has the upper hand and is really enjoying it". She thought of "Nirrti as a scientist and an explorer in a way" who "obviously has an end in mind that is nefarious". She found Nirrti's subtle sense of humor the most appealing. Samuda pitched the concept of the DNA machine for "Metamorphosis", its purpose and potential dangers, to the producers, but she did not pitch Nirrti as the Goa'uld who possessed it (co-writer and visual effects producer James Tichenor did).
Osiris, played by Anna-Louise Plowman (seasons 4–5, 7) – A Goa'uld based on the Osiris of Egyptian mythology. Season 4's "The Curse" explains that Osiris was banished in a stasis jar along with his queen Isis by his brother Seth thousands of years ago. Osiris escapes when Daniel's former archaeologist colleague, Sarah Gardner, opens the jar and is possessed. Osiris escapes Earth and is recruited to represent Anubis at a summit of the System Lords in season 5's "Summit"/"Last Stand". In season 5's "Revelations", Osiris locates the base of the Asgard Heimdall and is able to defeat and capture Thor, but is forced to retreat with the arrival of Asgard reinforcements. Osiris last appears in season 7's "Chimera", where she uses a Goa'uld memory device on Daniel to find the location of the Lost City of the Ancients in his mind. She is discovered and captured, and the symbiote is extracted from Sarah's body.
Ra, played by Jaye Davidson (Stargate), Jay Williams (season 8) – The alien villain in the film, based on the Ra of Egyptian mythology. Although the outline of Ra's original humanoid form in some scenes of the movie contradicts Stargate SG-1's definition of a Goa'uld, the series describes him as the most powerful and cunning of the Goa'uld, holding the title of Supreme System Lord. Ra's Queen was Hathor, his son was Heru-ur, and his brother (and enemy) was Apophis. As explained in the film and the series, Ra voyaged across the galaxy 10,000 years ago in search of a new host, discovered that the primitive humans of Earth were ideal hosts and eventually he seeded humans throughout the galaxy to serve as Goa'uld slaves (see Mythology of Stargate). A nuclear weapon kills Ra aboard his mothership in Abydos' orbit in the Stargate film, creating a power vacuum in the galaxy and drawing the attention of the other Goa'uld to Earth as the premise of Stargate SG-1. Ra appears in masked form in SG-1's season 8 time-travel episode "Moebius", and also briefly appears unmasked in the alternate timeline of Stargate: Continuum as one of Ba'al's lieutenants.
Sokar, played by David Palffy (seasons 2–3) – A System Lord who replaces Apophis as the principal enemy of SG-1 for the first half of season 3. He is named for the Seker of Egyptian mythology. Sokar's backstory is mostly revealed in dialog, and he only appears in person in the season 3 two-parter "Jolinar's Memories"/"The Devil You Know" (although his magnified voice is heard in season 2's "Serpent's Song"): Sokar once ruled the System Lords until an alliance including Ra, Apophis, and Cronus defeated him. Sokar was then forced to use an Unas as host body, and posed as the god of death on many different worlds, with Satan as one of his guises ("Demons"). Sokar slowly gains power in the Goa'uld domain in season 2, and to prevent Sokar from becoming unstoppable, the Tok'ra enact a plan in "Jolinar's Memories"/"The Devil You Know" to assassinate him. However, a disguised Apophis (who became Sokar's prisoner in "Serpent's Song") takes advantage of the situation and takes control of Sokar's massive army after the prison moon Ne'tu blows up with Sokar's ship in orbit. • David Palffy became involved with Stargate through the regular audition process. He remembers to have done automated dialogue replacement in post production for Stargate, but is not entirely sure if he provided Sokar's voice in "Serpent's Song" before being cast as Sokar in season 3. He was later cast to play Anubis.
Tanith, played by Peter Wingfield (seasons 4–5) – A Goa'uld symbiote incubated by the Jaffa priestess Shan'auc. In season 4's "Crossroads", the nearly-matured symbiote convinces Shan'auc to defect to Stargate Command and eventually to the Tok'ra, where he blends with the willing host Hebron. After the symbiote murders Shau'nac for betraying her true god, Sha'nauc's lover Teal'c swears revenge. The Tok'ra use Tanith to feed misinformation to the System Lords until "Exodus", where Tanith escapes and brings Teal'c to Apophis. Season 5's "Between Two Fires" reveals that Tanith has switched masters to Anubis, and Tanith commands an assault that annihilates the Tollan. In Tanith's final appearance in "48 Hours", Teal'c kills him by firing directly into the bomber's cockpit of Tanith's Al'kesh.
Yu, played by Vince Crestejo (seasons 3, 5–8) – The eldest of the System Lords, introduced as Yu the Great in season 3's "Fair Game" when he visits Stargate Command along with Cronus and Nirrti to negotiate Earth's entry into the Protected Planets Treaty. He is re-imagined in season 5's "Summit" as the Jade Emperor, the exalted Yu Huang Shang Ti, a separate figure in Chinese mythology. Yu is the only System Lord in season 5's "Last Stand" who opposes re-admitting Anubis into their ranks, and his forces manage to hold their own in the lone ensuing battle in season 5 and 6 despite facing superior numbers and technology. In season 6's "Full Circle", Yu convinces the other System Lords to join him in opposing Anubis, but Anubis decimates their collected fleet. Yu's First Prime, Oshu, reveals in season 7's "Fallen" that Yu's mind is failing due to old age and he is no longer able to take a new host. During negotiations on Earth against the threat of Ba'al in season 8's "New Order", Oshu must speak for Yu to hide Yu's further deteriorated mind from the other present System Lords. Yu is killed by Replicator Carter in season 8's "Reckoning" as the first act of her invasion of the Milky Way. Yu appears briefly in the alternate timeline of Stargate: Continuum as one of Ba'al's lieutenants.
Zipacna, played by Kevin Durand (seasons 1,3, 5) – A Goa'uld who once served Apophis. He is introduced in season 3's "Pretense" as Klorel's defender at a Tollan trial, while he secretly plots to destroy the Tollan ion cannon network. After this failed attack, Zipacna reappears in season 5's "Summit"/"Last Stand" and pledges allegiance to Anubis. He recruits Osiris into his service and commands an attack on the main Tok'ra base at Revanna, killing almost all the Tok'ra there. Zipacna and his armies are mentioned again in season 5's "The Warrior", in season 6's "Abyss" and in an alternate timeline in Stargate: Continuum.