|This article pertains to Xenogears: the sub-database of Xenosaga Wiki.|
The Mountain Cave is in the mountains near the Aveh-Kislev border. It leads to a plateau in the mountains that overlooks an area of the desert where Vanderkam's fleet was stationed. Fei also had to confront Elly and her squad of soldiers here in order to pass. Elly was driven into a psychotic fit when she used the battle enhancement drug "Drive" and wound up fighting a reluctant Fei and almost killing him with her Gear's AEROD weapons system.