However, Osiris subdues them by pumping poisonous gas onto their deck. Heimdall informs them that Thor is alive O'Neill and Teal'c ring onto Osiris' ship, while Carter guides them from the lab. SG-1 arrives at Heimdall's laboratory in a Goa'uld cargo ship, where they learn that Heimdall is researching ways to reverse the genetic degradation in the Asgard race, caused by repeated cloning. For the moment, he enlists SG-1 on a mission to save the Asgard scientist Heimdall before he is captured by Osiris' master Anubis. At Stargate Command, still grieving Daniel Jackson's recent death, the Asgard Freyr arrives with the news of Thor's defeat and that the Goa'uld have developed advanced technologies that threaten all of the worlds under Asgard protection, including Earth. The Goa'uld commander, Osiris, is defiant and for good reason: when Thor opens fire, his weapons fail to penetrate the Goa'uld ships' shields. An Asgard mothership commanded by Thor confronts two Goa'uld pyramid ships over an alien planet under Asgard protection.
