Ori

Millions of years ago, the Ori lived together with the Ancients as Alterans in a distant galaxy in the Stargate Universe. A split occurred and the Ancients began to devote themselves to science, while the Ori became increasingly religious. The Ori attempted to destroy the Ancients and to avoid a war, the Ancients departed their home galaxy for the Milky Way. Being almost equal in technology to the Ancients, they followed them to the Milky Way where some humans believed that the Ori were responsible for a plague that almost killed all the Ancients. Even though both the Ancients and the Ori eventually ascended, a device called the Sangraal (anti-Ori weapon or anti-ascended weapon) was built by Merlin (an Ancient) and used to destroy the Ori.