Anubis (Stargate)

Anubis is a Goa'uld that was exiled from the System Lords for crimes unspeakable even to the Goa'uld. Long thought dead, Anubis returned in the wake of Apophis' defeat and began to dominate the galaxy using advanced technology superior to that of the Goa'uld.

It is eventually revealed that Anubis is an Ascended being. According to the rules of those Ascended, they are not allowed to "accelerate the natural ascension process of those beneath"; however, Oma Desala broke the rules and helped some, including Anubis ascend. Normally, one must be pure of heart to be capable of ascension, but the evil Anubis managed to trick Oma Desala by using previously discovered Ancient research on ascension to "cheat" on Oma's spirituality tests.

Because of his evil nature, the other Ascended cast him down to a lower plane; however, they did not cast him entirely back to mortal existence, or interfere in his later actions, in order to punish Oma Desala for her actions. Anubis retained much of his Ascended nature, including a spirit-like body (later seen manifesting as smoky black mist) that he requires a forcefield to maintain in a humanoid shape. When he Ascended, Anubis gained the knowledge of the Ancientss, giving him the ability to build their advanced technology. Anubis used his technology to attack and seize resources from each of the Goa'uld System Lords, as well as to recruit exiled Goa'uld (such as Osiris, Tanith, and Zipacna) to his cause.

During the course of his galactic conquest, Anubis' most significant achievements included the successful destruction of an Asgard ship, the creation of a new, almost indestructible ground trooper (known as Kull Warriors to the Goa'uld and Supersoldiers to the Tau'ri), the destruction of the Tollan civilization as well as the near destruction of the Tok'ra, and the construction of a Death Star-like superweapon capable of destroying entire planets. Although the System Lords initially entertained the idea of accepting Anubis into their ranks, they eventually joined forces to oppose him, entering into a reluctant alliance with Earth and SG-1. This uneasy alliance succeeded in destroying Anubis' planet-killing mothership, but Anubis himself continued to control significant resources with which to battle his enemies.
Anubis finally launched an all-out attack against Earth using more than 30 motherships in the Season 7 season finale, "Lost City". His initial assault resulted in the destruction of a sizable portion of the military forces of Earth's major nations, but he and his fleet were ultimately incinerated when Jack O'Neill uses the planetary weapon of the Antartica Ancient outpost to defend the Earth.

Because of his immaterial, half-ascended nature, Anubis survived the destruction of his fleet and attempted to return to power after crash-landing on Earth. He manifested as an invisible energy that possessed various members of the SGC until he managed to escape through the Stargate in the body of Russian military officer Alexi Vaselov, only to find himself stranded and frozen on a remote ice planet.

Almost a year after being stranded on the ice planet, Anubis somehow escaped, reclaiming his fleet and Kull Warrior army from Ba'al and also making himself master over Ba'al (much to Ba'al's dis-taste). During the climactic replicator invasion of the Milky Way galaxy, Anubis learned of an Ancient super weapon that could be used to defeat the Replicators. However, the weapon would not only destroy Replicators, but would also wipe out all life in the galaxy. Even after the Replicators were ultimately defeated by SG-1, Ba'al, the Free Jaffa, and Daniel Jackson, Anubis continued to plan to activate the weapon and destroy all galactic life so he could re-build the galaxy to his own design. But midway through the battle to take the super weapon, Anubis disappeared, causing his soldiers to stop fighting. While Daniel Jackson was deciding whether to ascend for a second time, after his death to the replicators, he realised that the Ascended spirit of Anubis as well as Oma Desala were in his presence. Daniel convinced Oma to fight Anubis, which prevented him from continuing his plan in the non-ascended world. Although neither Oma nor Anubis could triumph over the other, as long as Oma continues to battle Anubis on the Ascended plane of existance, he can only ever fight her back and cannot return to the mortal world for the rest of eternity.

Despite his advanced technology and immortal nature, Anubis was limited in that he could not actually use his Ascended powers, as that would have caused the other Ascended to intervene as they did to Daniel Jackson when he tried to use his powers to interfere in mortal affairs.