10. The Slitheen
A family from the planet Raxacoricofallapatorius, these creatures are about as inspired as... well actually I really don't know! Green slimy gurgling things who explode when doused in vinegar, they are utterly pointless. I'm sure that a more believable alien race could have been conceived by the minds of the producers and writers, as opposed to something that farts constantly and makes crass jokes. The last time these creatures were funny was about five minutes after they appeared on screen. How exactly did they expect to go undetected? If a human such as Harriet Jones could sense something amiss, then surely they ought to have realised that The Doctor would follow the trail of fart gas to Westminster? I hope and pray that they have all been vinegarised into lumps of green slime for good. Perhaps their sludgy remains might make a decent and nutritious face mask of some kind? Gallifrey knows that Jackie Tyler could do with some.