5. Gort (The Day the Earth Stood Still)
*Disclaimer: At no point in this entry shall we acknowledge the existence of any form of The Day The Earth Stood Still other than the original 1951 film, for no other versions exist, so why bother bringing this up in the first place?* This film certainly stands proudly in the halls of famous and brilliant science fiction. When a spaceship lands in Washington D.C. panic surrounds the event. Finally, after much horror and some misunderstanding, we learn that the ship was sent to Earth with a message, but also a warning. Humanity's entrance to space has proven worrisome for more advanced races, since they've seen humans penchant for violence. So the man from another world gives warning: mend your ways or you will be destroyed. However, as famous as this film is, the one thing overshadowing all else is the alien's assistant, the giant robot Gort, who is so powerful humans are warned he alone could destroy the Earth. Also, one of the commands he's given has become iconic in its own right: "Klaatu barada nikto". Don't act like you've never heard that before.