Sure he doesn't start out as a villain - rather quite the opposite; the Stephen Merchant-voiced orb-like droid is one of the most charming, well-written and downright loveable characters in the history of the medium. However this makes for all the more memorable a turn when after a life of servitude and being resigned to only travelling where his rails would allow, he suddenly gets an overwhelming feeling of power thanks to some new hardware and sets about turning the tables on you right at the last second. How to finally take him down is one of the best Moments of the Decade, but it's in his playfully sinister taunts that build in their severity that you'll constantly be laughing at the whole situation, whilst also fumbling for a way to end his otherwise-inevitable reign of terror.
