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This article is about the Phi Excavation Site. You may be looking for the Phi Robotics Center.

The Phi Excavation Site is an Alterra installation set up to uncover and research the Frozen Leviathan. It is located in the western Glacial Basin, underneath a large mountain.


The excavation site is a cavernous space that shows signs of a rock collapse, with loose rock ranging from small pebbles to large boulders scattered about the area. At the back of the cave is a massive wall of ice that has trapped the Frozen Leviathan inside.

Alterra had a strong presence here, having set up a catwalk in front of the ice wall, with the lower floor serving as a makeshift laboratory. An elevator leads up to a room that was cut into the ice, where the head of the creature can be observed up close. A similar tunnel can be found back on ground level, where one of the creature's claws was being observed.

A Prawn Suit, forklifts, and a large crane can be found here, having all been used to excavate the creature. A significant amount of Floodlights and Light Sticks can also be found here, illuminating the space.


Prior to Below Zero

An an unknown point in time after Alterra's arrival on Planet 4546B, the cave was discovered by Alterra employee Fred Lachance. Shortly afterwards, the cave was made off-limits to most employees, and was put under heavy surveillance, with Parvan Ivanov working as security.

Alterra showed extreme interest in the Kharaa Bacterium that had infected the creature, and sent Danielle Valenti and Vinh Pham to harvest samples and bring them back to Omega Lab for further testing.

When Samantha Ayou learned of what was going on at Omega Lab, she made plans to prevent Alterra from harvesting any more samples. Acting on her own, she attempted to cause a cave-in at the excavation site, but was interrupted by Parvan. It was upon Parvan's intervention that the cave entrance collapsed, killing both personnel. Alexis Riedell was later sent to investigate the cause of the collapse, linking it to the sabotaging of Omega Lab.

During the Events of Below Zero

Following the death of her sister, Robin Ayou arrives on 4546B to learn more about the cause of Sam's death. Eventually, the trail of evidence leads her to the Phi Excavation Site, where she finds the site of Sam's death, as well as her necklace nearby. From here, Robin can either ignore the Frozen Leviathan's infection, or complete her sister's work and cure it. In order to do the latter, the player will need to find the Kharaa Antidote, which was hidden away by Sam.


Main article: Achievements

Spoiler alert: The following section contains story related material.
Finding the Cure Achievement.png Finding the Cure

Use the antidote.

How to obtain: Eliminate the Kharaa Pustules on the Frozen Leviathan by using the Kharaa Antidote.