Many cryx seem to carry a shadowy darkness around them.  Though in some it is barely observable until its too late.  Cryx seem always to be in dark shadowy area and their lairs seem to be completely submerged in a shadowy unnatural darkness.  Many have compared it to the Plane of Shadows or more closely, the Shadowfell.  Suggestions have been made that perhaps the Cephylix and their Crix abominations do originate form the Shadowfell though no connection with Zon-Kothon has ever been made nor to Cephylix or Crix seem to associate with any deifiec power or religion. The darkness of the cryx defies any magical illumination and non magical illumination becomes so faint as to be barley discernible.  Those races blessed with vision to see in total darkness are even hampered by the darkness and their natural sight  proximity is halved.  Those that have vision to see in star light are almost completely blinded able to see only about 10 feet in front of them.  Those with no natural aptitude to see in darkness our unfortunately completely blinded.  It is unknown if the darkness is a manufacture of the Cephylix directly or a type of taint they carry form their plane of origin. The Cryx Darkness concentrates and spreads in an area that is heavily inhabited by cryx.  The secondary effect of this darkness seems to plunge the area into cold temperatures and also effects all flora and fauna in the area killing it.  The land becomes a barren wasteland of shadowy darkness.  This can spread for many miles depending the concentration and length of stay of the Cryx and Cephyix . Cryx darkness also appears to cling to any creation of the Cephalyx including their alchemical and mechanical creations such as Obelisks, Pylons and Pylon Energizers.