Architect Phase Gate Facility

This unnamed Alien Base is set to appear in Below Zero. What purpose it serves and why it was constructed is currently unknown.

The exterior is built similarly to that of the Primary Containment Facility in the Crater, as seen in the concept art.

Story
During her search for Jo Jeffreys, Robin Goodall will stop by the Alien Base, only to be denied access by an unknown voice, who threatens her. Taken aback by the facility knowing her name, Robin reports to her sister, Sam Goodall, who warns her that an electrical storm is coming, but lightning confirms that it's already arrived. On her way out of the cave, the electrical storm renders the cave unstable, and an avalanche blocks the cave entrance and destroys the Research Base.

Lower Section
The lower section of the Mountain Cave Base is accessed via an ice cave tunnel. At the beginning of the story, the interior is inaccessible as Al-An restricts access to the inside. At a later point in the story, presumably after Al-An has been given a physical form, the force field will be shut off, granting access. Not much is known about the contents of the base, except for a single elevator leading to the upper section of the base.

Upper Section
The upper section of the Mountain Cave base is accessible only by the lower level's elevator. In-development footage shows that a large amount of the base is jutting out of the mountain, forming what appears to be a balcony. The exterior of the upper section is far larger than that of the lower section, and it is possible that it may be visible from the surface. According to developer notes, the upper section features an Alien Arch leading to an unknown location, as well as a terminal that ends the game. It can be assumed that the Mountain Cave Base is the endgame.