The Mountain Stronghold was the fortress for the Voya Nui Resistance Team. According to the Matoran, it was built in the time before Voya Nui split off from the Mainland. It appeared on VNOG, on Inika Island Assault where Avak appeared as boss, and on Matoran Escape, where Thok was the chapter boss. It was destroyed when Voya Nui returned to the Southern Continent.