Morton Koopa Jr. aka Bigmouth Koopa Biography
Morton Koopa Jr

Character fact sheet

Name: Morton Koopa Jr aka "Big Mouth Koopa"

First Appearance: Super Mario Bros. 3 (1988)

Home: Castle of Koopa

Voiced by: Lani Minella

Associates: King Koopa (Dad), the other Koopalings (siblings)


Morton Koopa Jr. is the second youngest of the Koopa kids and the largest of the bunch - despite this however he isn't as powerful yet as Ludwig who is very smart or Roy who is very strong. Like all the Koopa kids, Morton is named after a celebrity, Morton Downey Jr. in his case. As he gets older his powers are expected to become more potent.


He lives at the castle of Koopa with all of his siblings & his dad King Koopa whom he refers to as King Dad. Despite being in possession of a magic scepter Morton's choice of attacks in the Mario series of games are usually centred around slamming the ground from a height or trying to land on and flatten the Mario's completely. He is also capable of walking straight up walls and for a brief period even walking along the ceiling.


Morton is the only Koopaling that is a shade of grey/brown in colour, he has a white head and a mark on his face which resembles a star. He takes various traits from the other Koopa's for example:-

  • Circular shaped small eyes - similar to Ludwig's.

  • He is a similar size to Ludwig and Roy Koopa.

  • His eyebrows bare similarity to those of Wendy O Koopa's in the fact that they protrude from his face

  • He has four teeth that are very fanglike - much like Iggy Koopa's.

A video from the writers of the Adventures of Super Mario Bros. 3 showing the way Bigmouth or Morton Koopa Jr. is meant to be portrayed as a character and the concept behind him.


The adventures of Super Mario Bros. 3 wrote about Morton Koopa Jr's personality and mannerisms as below:-

Big Mouth just can't stop blabbing, and his twisted talent is insult. His cutting remarks can even reduce his father to tears. Big Mouth's got a chip on his shoulder the size of the Doomship. He would never admit he was wrong, even though he usually is.


He thinks he knows everything about everything, but what he knows is all wrong, and he always blames the other guy for his mistakes. Big Mouth loves to stir up trouble, and has a needling probing attitude that always gets it. He holds grudges against the whole world.


Morton like all the other Koopa Kids was named differently in the Adventures of Super Mario Bros. 3 cartoons to a name which reflected his personality in this case he was known as "Big Mouth Koopa Jr".


Some quotes from Morton Koopa Jr. from the Adventures of Super Mario Bros. 3

  • "That's Prince Hugo the Huge! The new ruler of Giant Land! They say he's the biggest, toughest, bravest prince ever! Even for a giant, he's a giant." - Sneaky Lying Cheating Giant Ninja Koopas

  • "Yeah, and they're gonna pick you to be their leader! Isn't that always the way? Treat people lousy, dump garbage on their heads and they'll follow you anywhere!" - Recycled Koopa

  • "Have a good time! Have a nice day! Sayonara! So long! Ciao! See you later, alligator! Ciao! Bon voyage! Hasta la vista! Be sure to write!" - Send in the Clown.

  • "Let's do an ambush..." - Do the Koopa

  • "You're a royal pain!!! And we need you'r cage for our prisoners!!!" - Sneaky Lying Cheating Giant Ninja Koopas


The obvious enemies of Morton Koopa Jr are the Mario Brothers, Princess Toadstool - but not limited to those select few, Morton hates everything and everyone and has a real vendetta against the world.



He doesn't really have any, like anyone who spends the entire time that they're awake insulting people and takes great pride in it, Morton Koopa Jr aka Bigmouth Koopa Jr is not in line to win any popularity contests any time soon. His siblings put up with him for the best part, but only because they have to live together!



Since his original appearance in Super Mario Bros. 3 Morton Koopa Jr along with the rest of the Koopa kids has antagonised the Mario gang whenever the opportunity arises; He took control of a castle in Donut plains in Super Mario World, overthrew the Sultan of Desert land in Super Mario Bros. 3 and took over his castle, he appears as a boss at the end of world 6 in New Super Mario Bros. Wii on a floating platform floating in lava.


He has also made appearances in spin off titles such as the Edutainment title Mario is Missing where he comes to earth with his dad King Koopa to help him steal artefacts.

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