Mysterious creature spotted in the background of Zelda: BotW screenshot

It seems like Nintendo has hidden all sorts of secrets in their trailers and screenshots. In Nintendo's upcoming Wii U title, The Legend of Zelda: Breath of the Wild, it has been reported that a large, mysterious creature can be spotted climbing up a mountain in one of the official screenshots. What do you guys think this creature is, and do you think that this creature could have a significant impact on the game?