Dalek 4 was among the Dalek force which invaded Trodos. It was one of five which followed the Dalek Supreme's lead into the Trods' subterranean city. Dalek 4 was sent alone into the city as bait and successfully lured the Second Doctor who obscured its eye antenna with his hat before using his recorder to penetrate its inner hearing system, rendering it berserk. (COMIC: The Trodos Ambush)
Tardis