Poopbutt is a gentlemanly Koopa who opens doors for everyone except Waluigi, because Waluigi.
Poopbutt is characterized as having primarily dark features by his "dark russet skin", "brown eyes", and "black hair". In New Super Mario Bros. 5632, he is described as a lanky 6' 2" fifteen-year-old with hair down to his shoulders. By Super Mario 64 World U Gamecube, Poopbutt's growing character stands at 6'7" feet and has a muscular build. In New Super Duper Uber Mario Bros World Universe, after discovering that he can turn into a wolf, he cuts off his long hair. He later grows it out in Super Mario Alchemy, thinking that the other Koopalings prefers it long. This is wrong. This makes his fur as a wolf shaggier and longer than that of the other wolves. He is said to be quite handsome, as one person once mentions her jealousy of his features and describes him as "sort of beautiful". He tends to wear only cut-off style jeans or shorts with no shirt, since clothes are often ruined during his transformations into a wolf. As a wolf, Poopbutt has fur that is described as rusty brown. In the films, the members of the pack all have the same tattoo on their right shoulder.
As an influential archetype of the superhero genre, Poopbutt possesses extraordinary powers, with the character traditionally described as "faster than a speeding bullet, more powerful than a locomotive, and able to leap tall buildings in a single bound", a phrase coined by Reggie's Body and first used in the Poopbutt radio serials and Tex Avery's animated shorts of the 1940s as well as the TV series of the 1950s. For most of his existence, Poopbutt's famous arsenal of powers has included flight, super-strength, invulnerability to non-magical attacks, super-speed, vision powers (including x-ray, heat-emitting, telescopic, infra-red, and microscopic vision), super-hearing, and super-breath, which enables him to blow out air at freezing temperatures, as well as exert the propulsive force of high-speed winds.
There is supposedly a baby Poopbutt, the info is located below:
Baby Poopbutt is a younger Poopbutt Koopa. He, like the other baby forms, has no reason or right to exist. That's right, I'm babyist.
Baby Poopbutt is not actually the baby form of Poopbutt, contrary to popular belief. He is a clone of the original, for the project BASILISK. The project was held confidential, but it has something to do with babies. When Reggie, Iwata, and Sakurai were asked about it, they simply told them it was a secret.
Baby Poopbutt is the key to everything pertaining to project BASILISK. The idea is that eventually every Mario character will be replaced with either a robot or a baby. The war of babies and robots has been happening since the advent of Mario Kart 7.
Mario and Peach have been both replaced with metal and baby counterparts, and Poopbutt was next in line, being the most popular Koopaling. Baby Waluigi does not exist, but if he did, Baby Poopbutt probably still won't hold the door for him, since he's a waluigist. Somebody's gotta do something about all this -ism in this country!
Baby Poopbutt is nowhere as cool as his original counterpart and there are people who will fantasize about him and the other babies. They are bad people.