Complex sentence: Mr. Mercer uses the brainwaves to develop a serum that reconfigures the brain so one is able to use the Healing TouchHe than teaches the candidates teaches them how to control it, including Derek's student Adel Tulba.
Split into simpler sentences: Mr. Mercer uses the brainwaves to develop a serum that reconfigures the brain so one is able to use the Healing Touch. He teaches the candidates how to control the Healing Touch, including Derek's student Adel Tulba.