The Foothold Aliens infiltrated the SGC by disguising themselves as the members of SG-6. (3.14 "Foothold")
The name of this alien species has not yet been revealed, but they are believed to be from P3X-118. They spoke a language made of grunts, shrills, and clicks and bled purple blood.
They infiltrated the SGC by posing as members of SG-6, using technology which allowed them to transmit the image of a person's physical form, as well as link to that person's mind. In their attempt to mimic Carter and Teal'c, they discovered that former Goa'uld hosts and Jaffa were resistant to their technology. The alien which took Dr. Fraiser's identity conducted studies on Carter and Teal'c (as well as Teal'c's symbiote) to understand more about their physiologies.
Carter and Teal'c were successful in getting away from the experiments, but Teal'c was recaptured after helping Carter escape. Carter made it to Washington, D.C., where she met with Col. Harry Maybourne of the NID to inform him of the foothold situation at the SGC. Maybourne talked with Gen. Hammond and agreed to get Carter to return to the SGC, believing that she was suffering from the side effects of a chemical leak at the SGC. The Gen. Hammond with whom Maybourne spoke was actually the alien impersonating him, but Maybourne was not aware of this. The aliens impersonating Jack and Daniel met with Carter and Maybourne after Maybourne's phone conversation with Hammond. They all convinced Carter to return to the SGC.
Even though he had his doubts, Maybourne arranged to have several special forces personnel target the SGC if he was not heard from in a certain amount of time. Maybourne took Carter back to the SGC on a private Air Force airplane. During the flight, Carter and Maybourne discovered that Jack, Daniel, and Major Paul Davis were all aliens. Carter figured out that a certain frequency emitted by the airplane's engines would interfere with the images the mimicking devices projected. She took the mimicking device which projected Daniel's image with her into the SGC to move among the aliens undetected.
Because the aliens which were impersonating Jack and Maj. Davis were killed on the plane, Jack and Davis woke up from their stasis at the SGC because the link to their minds were broken. Along with Carter, Jack and Davis began to regain control of the SGC. Soon, Maybourne's special forces were in the SGC and the aliens were forced to run. The aliens attempted to get through the stargate, but not all of them made it through. The ones which were left behind committed suicide.
None of the aliens left on Earth survived, but their technology was taken to Area 51 where scientists tried to duplicate the mimicking devices. (6.14 "Smoke And Mirrors")
None of the aliens were given names, but many of them impersonated SGC personnel:
- The alien which took on Dr. Janet Fraiser's identity was one of the leaders. "She" conducted the experiments on Carter and Teal'c concerning their resistance to their technology, as well as supervised the mimicking procedure.
- The alien leader (seen in his alien form) conducted the evacuation of his troops once their presence was discovered and Col. Maybourne's team of special forces began to take back the SGC. When his escape through the stargate was thwarted, he self-destructed, taking all of the aliens still at the SGC with him.
- Some of the aliens escaped through the stargate and took with them the knowledge of those SGC personnel they impersonated. General Hammond locked out P3X-118 from the dialing computer, but this doesn't necessarily mean that the aliens originated from there.
- No known alliances. They seemed to be completely uninformed about Goa'uld and Jaffa, since they were not familiar with symbiotes.
- Tau'ri - The Tau'ri are now an enemy of this race because of their attack on the SGC and their attempt to take over the world. The address for the planet where they were met (P3X-118) has been locked out of the SGC's dialing computer.
--DeeKayP 17:16, 17 Jul 2004 (PDT)