Van Cassadine energy

Van Cassadine energy was a "nasty" form of energy which was used by the Voord and other species with little concern for planetary environments. The Eighth Doctor was able to taste it in the air and it gave both Daniel and Matilda Gregson headaches. (AUDIO: Beachhead). The Ninth Doctor planned to use Van Cassadine energy to generate a Delta Wave to destroy the Daleks using Satellite Five as a transmitter. Captain Jack Harkness described its effect: “A wave of Van Cassadine energy. It fries your brain. Stand in the way of a Delta Wave and your head gets barbecued.” (TV story: The Parting of the Ways)