5. The Slyther (The Dalek Invasion Of Earth)
Maybe part of the problem of the Slyther can be chocked up to unrealistic expectations. We hear about the horrifying Slyther, used by the Daleks to guard mines, far before we actually see one. And then when one finally lumbers by, slow and completely nonthreatening well, its a little underwhelming. Long tentacles stretch out haphazardly, with the actor encased in the costume groaning pathetically, the Slyther is a mess. But its an endearing mess.