2. The Daleks - Dalek
Alright, I sort of already covered the Daleks, but I thought that those Lego Daleks were special enough to have deserved their own special place on this list. I should also disclaim that--like the Cybermen and the Master--I don't think that the Daleks need to stay away forever. Just for a while. The Daleks were great in Season 1, if for Nine's (and Christopher Eccleston's) reactions to them than nothing else. Of all three Doctors so far, Nine is the one who has most convinced me that the Daleks are actually the devastating killing machines that warranted the destruction of Gallifrey and as they are so frequently described to us. They were frightening, and they gave Nine what was one of his best moments when he tells Rose--then a captive of the Daleks--that he's coming to get her. And he does, because he's Nine, and Nine is awesome. The Daleks were even still good in Season 2, when their single storyline return in "Army of Ghosts"/"Doomsday" had devastating consequences for the Doctor. Also for the innocent population of Great Britain. But we mostly cared about the Doctor and--if we had hearts in our chests--cried buckets at the Bad Wolf Bay scene. And then there came the "Daleks in Manhattan"/"Evolution of the Daleks" two-parter in Season 3, and it's all gone downhill from there. While it was a nice change for them not to be the season's ultimate bad guy yet again, those two episodes episodes were pretty bad. More people were probably impressed with "The Idiot's Lantern" than these two episodes, both of which really should have taught Moffat never to make an episode with "in Manhattan" in the title. Season 4's "The Stolen Earth"/"Journey's End" was slightly better with regard to the Daleks, but there are only so many times that there can be devastating Dalek genocides that are definitely totally 100% permanent this time before the emotional impact is gone. And then there were the Lego Daleks.