Monolith Base served as the new main base of operations for the fictional Cobra Organization featured in the G.I. Joe universe. Located in the mountainous regions just north of the capital city of Badhikistan, the base itself was considered by many of Cobra's elite to be heavily fortified and near invincible. After Cobra Island was abandoned, Cobra Commander ordered all Cobra assets moved to Monolith Base. From there, the Commander initiated the first test of the Tempest Weapon system.
Before the weapon could be used further, a 12 man GIJoe team was able to not only take out both Cobra's Air and Sea forces, but also successfully penetrate the bases' main defenses and work their way up to the control room. With security breached, Cobra Commander fled along with Tomax, Xamot and several Crimson Guards. Many Cobra agents were apprehended in the fall of the base and along with the subsequent liberation of Badhikistan, the Cobra organization suffered major losses from which it has yet to recover fully from.
It should be noted that while the Commander had ordered all Cobra agents to the base, it is very likely this did not occur because following the base's destruction, a number of Cobra cells were still active worldwide. This, combined with the fact that the 12 man GIJoe team easily disabled the Air and Sea forces as well as work their way to the command center indicates that not all Cobra agents had been relocated to the base.