Keystone

A keystone is a piece of Praxian technology.

History
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 holomap, 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.

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A real keystone emits a steady dose of 2.2 rads of gamma radiation.

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