What is the significance of Pink Bunny in Silent Hill: Revelation?

I believe its a reference to the third installment of the Silent Hill video game series. The amusement park features a Mascot called Robbie the Rabbit. His role in the film would most likely be a homage to the video game simply creating an unease to the viewer.

Information about Robbie the Rabbit

For the most part, his role seems to serve little more than to provide an ambiguous level of unease to the player, due to the odd nature of his existence within the world of Silent Hill, his bright colors contrasting from the rust brown and dark red of everything else, and his recurring cameos.

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Other details

Being nor an actual monster or enemy, Robbie the Rabbit has developed a following all his own. First appearing in Silent Hill 3, Robbie can be found in six following games and the sequel movie. Robbie’s appearance as the large, blood splattered mascot of Lakeside Amusement park helps to develop an uneasy setting with the contrast of his bright colors to the grim world around. It is never explained weather there is a wearer to the costume, or even Robbie is sentient is anyway, but he plays almost like an omen and water to the Silent Hill universe. A pink, rabbit head shaped window sticker on a car in the original Silent Hill that foreshadows to his existence.

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Hope that helps!