Proof Fragments

Proof Fragments are quest items required to construct the Limbo Theorem key (not to be confused with the quest key).

Characteristics
Supposedly, these fragments transmits the signals all across the system and may be found by investigating the wavelength. It is described by Ordis that the frequency--while constant, is far too weak to be caught by the Liset's antenna and that it would require a sophisticated antenna to fully catch the wave such as the satellite found in the Archwing Interception mission.

In a way, the Proof Fragments themselves can be interpreted as the remains and the relic of the original Limbo in the form simlar to cosmic background radiation, as the fragments can be engineered into a theorem which leads into another Limbo piece.