SG-X was a team composing of Humans who once served Apophis. The team was able to acquire the same uniforms and weapons as SG teams from Earth. Their purpose was to be trained and on Apophis' orders, invade Stargate Command and Earth. SG-1 encountered the team and managed to convince them that Apophis was dead which ultimately prevented SG-X from attacking Earth. (SG1: "Rules of Engagement")