Mort is a glaucous grey friendly-to-the-extreme boy attending Mu Elementary School. He first appeared in the web episode "Concrete Shoes". For the television series, he was given a background and a personality, but he never spoke and this personality was never shown.
Mort was first seen in episode nineteen of the web series, "Concrete Shoes", being picked up by an ice-cream fiend. He is only seen rarely in the web series, but it was announced that he would become more developed in the television series. However, he has never spoken, although he screamed and hid in a trash can in the episode "Pony". He appears briefly in the TV series and has only been seen in the background.
According to Nick's site, he is a boy who gives nonsensical advice (such as cooking rocks) but so far in the series this has not been shown. He has a fear of soda, but "a mysterious and tragic love of soda cans".