Revelation of the Daleks features the Daleks taking over a suspended animation facility and turning the inhabitants into Daleks. Until that Hell, theyre kept in an extra special Hell of having a hateful imitation American DJ talk to them for all of eternity. Its like training them to want to kill all life. Even Davros hated him but needed him as a distraction. It shows more than all the Nazi imagery in Genesis of the Daleks that hes truly sadistic scum. When they come to finally kill him, he decides to inflict more of his music on them by using an ultra frequency gun of Rock n Roll!. Presumably it kills them by overloading them with PTSD.