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A local teen gets the high score on an arcade game, and he wins a real life replica of the main enemy in the game. It arrives at his door one day. At first he and his (I'm pretty sure girlfriend, maybe sister?) are enamoured with it, but then it tries to kill them and their friends and family. There is one scene I remember where the robot picks up a long kitchen knife in its arm, and it rotates quickly.
I thought the movie was called "Hover" for some reason, but that's not it. The robot was short and red I think.