Because he remembers there's a time limit, so he speeds up, then he gets distracted by the things in a level, so he forgets to mantain his speed, then he remembers again, so he speeds up again, only to get distracted again by the level, and lower his speed. Being Chip is not easy.
Why do we refer to Chip's direction as North, South, East, and West, instead of Up, Down (Or Forward, and Back), Left, and Right?
Why do we refer to Chip's direction as North, South, East, and West, instead of Up, Down (Or Forward, and Back), Left, and Right?