O7 is an allegedly discontinued vocational code in the Systems Alliance military. The "O" designates covert operations and the "7" refers to the highest level of proficiency. The goal of the O7 Program was to train teams of highly loyal commandos and operatives. The project began shortly after the Skyllian Blitz. During training, the O7s were subjected to heavy psychological conditioning, which often led to mild xenophobia, particularly towards batarians. The O7 program's first major combat operation was the Battle of Torfan. O7 commandos committed some of the most brutal actions of the conflict. After Torfan, the Alliance decided that the O7 program was a mistake, and attempted to bury the project. Most of the O7s left the Alliance shortly after Torfan, with a significant number joining the human supremacist organization Cerberus.