The facility is used primarily as a testing facility using the test subjects. It is fitted with the technology required to change the test subject's Breed and sex, to allow testing of drugs and other produces across a wide range of genetic structures, to make sure they are safe for the general populace of other worlds.
The existence of the facility and the nature of biological, chemical and other tests on sapient creatures is a closely guarded secret, as the knowledge of the facility's existence and the basics of what they do would cause outrage across multiple societies.
The facilities activities also extend far beyond these relatively simple parameters, and below the surface is rife with problems, with many sections of the facility abandoned, sealed off and stricken from available maps, with the nature of what occurred in those old sections expunged from all but the highest security clearance administrators.
Test Subjects are introduced to the testing environment through a collection of entrance rooms for where they choose their breeds, genders and may be provided with wigs or other articles of clothing. They are allowed to wander the hallways and gather in the large central hall for socializing when they are not taking part in tests.
A network of cave systems also exists around the underground facility. These caves can be accessed from some areas as demonstrated by CAT, and test subjects within the cave systems fall off the network, going offline and their locations remaining unknown and unable to receive instructions until they re-enter the facility.
An unknown quantity of derelict and abandoned rooms and hallways exist that are stricken from the official facility maps. The nature and original purposes of these sections are unknown, but are shown to be grizzly and dangerous places. TS2 and ETLUC started out with access to one such area. Lighting was in a low power state, and one adjacent room was filled with blood of unknown age.
The location and nature of E.D.E.N. are unknown, but it exists and is tied to ETLUC's purpose.