The Ori are Ascended Beings who manifest themselves in a wall of fire in the City of the Gods on the Plains of Celestis in a far galaxy, assumed to be the original home of the Ancients (who were called the Altera when they left that galaxy and made a new home in the Milky Way Galaxy). The Ori claim to be gods and the creators of all humanity and are served by those who follow their religion, called "Origin", which is put forth in The Book of Origin. The Ori call the Alterans "evil" because they have kept the human life of the Milky Way a secret and withheld the "truth of the universe" from them. The Ori now know of humanity's existence in the Milky Way and are sending their representatives, advanced humans to whom the Ori have given great powers, to show the Path to Enlightenment. If humans of the Milky Way reject Origin, they will be destroyed.

Choose to ignore the Illuminaria Galaxy because the habitants of that galaxy would be able to defeat their soldiers within minutes of their arrival into it.