Stargate: Every System Lord Ranked Worst To Best
2. Anubis
Anubis was probably the greatest, in that he was the most evil, of all of the System Lords in history. His crimes were so great that the Goa'uld banded together to bring him down, which is something that SG-1 have trouble comprehending - even the Goa'uld have limits.
Throughout his history, he has risen and been vanquished a number of times. It was Ra who primarily held him at bay (thanks a bunch, Jack O'Neill), though his last defeat before his great return resulted in him allowing the other System Lords to believe he really had been killed. This allowed him to concentrate on his studies of the Ancients, and the secrets of ascension. He tricked Oma Desala into helping him ascend.
He was refused the full power of ascension by the other Ancients, yet he was allowed to remain partially so, as punishment to Oma. He was also allowed to retain whatever information he could have discovered as a Goa'uld - giving him a distinct tactical advantage over the remaining System Lords.
With the deaths of Ra, Apophis, Cronus and Heru'ur, the stage was set for a return. He announced himself slowly, letting his torchbearer Osiris spread his message. A majority of System Lords voted to allow him to return to their ranks.
Once back, he was seemingly unstoppable. His Ancient knowledge allowed him access to technology that outstripped even the Asgard. However, it was Ancient technology that would spell his doom. Jack O'Neill, making up for clearing the path for him, downloaded the Ancient knowledge into his mind and, through this, was able to locate a weapons platform in Antarctica - fully armed, and ready to destroy Anubis's fleet.
Anubis himself survived, creating havoc for a final year before he was eventually held in a permanent battle with Oma Desala.