SG-12
From SGCommand
The teams SG-3, SG-12 and SG-15 were called in by General George S. Hammond when SG-1 was negotiating with what seemed to be a hostile human race, called the Aschen. One year later, in August 2002, they were totally wiped out at the Tok'ra base when it was destroyed by Anubis' fleet, according to Major Pierce of another SG team. (SG1: "2001", "Allegiance")
The team was apparently reconstructed at a later date. In 2003, they accompanied Major Samantha Carter and Teal'c to planet P2A-487 when assessing what could be done to restore Daniel Jackson's health. It was temporarily lead by Cameron Mitchell in 2005 when investigating a religious man connected to the Ori on the planet P3X-421. (SG1: "Lifeboat", "Origin")
They were also sent as back-up with SG-10 for SG-3 when SG-1 went missing. (SG1: "Zero Hour")
