A keystone is a piece of Praxian technology. As its name suggests, it serves the function of being a 'key' to unlock certain Praxian technologies. A keystone is needed in order to progress further into the holographic map, revealing coordinates for a gateway. It is also needed to activate and unlock a gateway.
To find a keystone, you must first have a holomap. When properly using a holomap, it will direct you to its missing piece (a keystone) that is located at a pedestal location. Once that keystone is retrieved and inserted into the holomap, the holomap will then direct you to its corresponding gateway into Hollow Earth.
History[]
Season 3[]
| Episode 3x07 - "Breach": to be added | |
| Episode 3x09 - "Vigilante": A real keystone emits a steady dose of 2.2 rads of gamma radiation. | |
| Episode 3x10 - "The Hollow Men": to be added |
Notes[]
- It is unknown if a particular keystone is assigned to a certain gateway and or also holographic map, making keystones non-interchangeable.
- The number of keystones / pedestal locations on the surface is unknown.
- The holographic map does not use active GPS location to find a keystone. Instead, it pulls from whatever coordinates someone had previously input into the holomap database that they had designated as a pedestal location for a keystone. This is evident when Helen Magnus and John Druitt are sent to Khövsgöl Province in Northern Mongolia to find that the keystone stationed there had been taken several decades prior, eventually ending up in the hands of a seralops in Hong Kong.[1]