When he was in his pre-teen and teenage years, he had brown hair and braces.
In "A Skips in Time", "Rigby in the Sky With Burrito", and "Regular Show: The Movie, high school Mordecai was seen wearing a white t-shirt with a red collar and sleeve cuffs with the words "Brain Explosion", the name of his favorite band, written on the front, with grey jeans and red sneakers.
He is a serious person and wants people to do the right thing.
It is also proven that he is fond of the word "dude" and the saying "oooooooh!
Rigby has been Mordecai's best friend since they were toddlers.
The two are virtually inseparable, always finding ways to forgive any breaks in their friendship.
His dark gray nose is found on his grey beak between his two eyes.Instead of getting outright angry, he asks Mordecai what his problem was.He then later apologizes to Mordecai about what he said.Mordecai is the tall, responsible, mannered one, while Rigby is the short, immature, energetic one in the duo.
They both work at the park together with Benson as their boss.Two white lines are found on both of his wings with two thinner, black lines on each of his fingers and one stripe of each of his thumbs, and three tail feathers, each with two black stripes.