Morton Koopa Jr.
Morton Koopa Jr (New Super Mario Bros U)
Morton Koopa Jr.'s artwork from New Super Mario Bros. U
Series Mario series
First game Super Mario Bros. 3
Species Koopa
Voiced by Dan Hennessey (DiC cartoons)
Lani Minella (2009-2013)
David Cooke (2014-present)
Quotes • Gallery

Big Mouth in the Super Mario World cartoon.

Morton Koopa Jr., also known as Big Mouth Koopa Jr. in the Mario TV series, was originally one of Bowser's children, before the idea was retconned into being a member of the elite seven-clan team, known as the Koopalings . His first appearance was in Super Mario Bros. 3, and he later appeared in Super Mario World, Yoshi's Safari, Mario & Luigi: Superstar Saga, and New Super Mario Bros. Wii.


Morton is a large and burly brawler, Morton has a pale-grey head with black hairs on it. The most obvious difference is that he has grey skin, a dirty-white belly, when compared to his sister and brothers, who has yellow skin and a lemon coloured belly. He has 4 sharp teeth, two handcuffs and his shell is grey with spikes surrounded by white rings. He also has a four-ribbed padded stomach and padded feet. He has a magic wand that creates spiky balls. In Super Mario World cartoon Morton counterpart is named Big Mouth, he's much shorther and thinner than his main video game counterpart, his eyes are much much larger, and he has purple eyelids, Big Mouth also has has a purple shell instead of a grey shell like Morton.


Super Mario Bros. 3

In this game, Morton, along with his siblings conquered Desert Land and took their ruler's magic wand, which he used to turn him into a spider (a Hoopster in the remakes). Morton's troops, however, was defeated by the Mario Bros. Morton then came face to face with them often do low jumps wand firing magic blasts, unlike other appearances Morton in his Mario 3. case couldn't shake the floor like his older brothers Roy and Ludwig. Morton was eventually defeated and abandon the wand.

Super Mario World

In this game when Bowser conquered Dinosaur Land he left a captured Baby Yoshi egg in Donut Plains were he left Morton at his castle to guard this piece of land so The Mario Bros. and the new friend, Yoshi. Like Super Mario Bros. 3 his troops failed and had to face his foes face-to-face once again. He attacks by climbing up walls while trying to crush Mario or Luigi. The floor will shake causing a short stunning to either Bro. unless they jump. It takes three hits to defeat Morton in this game much like Super Mario Bros. 3.

Yoshi's Safari

Being in charged of guarding a crystal gem Morton (thanks to Iggy) mechanical frog guarded it, for a brief time. Morton faced Mario and Yoshi again. He threw bombs and hoped a lot in his mach. Later, he was shot by Mario and Yoshi by the Super Scope and he was defeated.

Mario & Luigi: Superstar Saga

Morton only had a cameo battle. Originally ordered by Bowser to guard the castle, Morton was hypnotized by Bowletta along with his siblings to fight Mario and Luigi. Before battle Morton would ground pound cause paralyzing waves, Mario and Luigi eased out of it. Morton repeated this in battle and spat fireballs, but was defeated after a while.

New Super Mario Bros. Wii

After nine years of being ignored, Morton reappeared in New Super Mario Bros. Wii. He disguised himself in a cake and kidnapped Princess Peach with the help of his siblings. Morton was dropped off at World 6 where he battled at his tower being fought by the Mario and co. he used magic blasts and his newly ground pounding ability. Though when stomped on his shell, he is hard to dodge especially if the player lands on the platforms he/she has dodge the spiked pillars. After being defeated, he retreated to his castle, being fought again. Kamek casts a spell to make Morton when he ground pounds the floor goes up and if Mario is on the floor when he ground-pounds loses a life. When Morton is defeated again, he survives and heads to World 8, where he helps Bowser onto his stomach, only to have the castle fall down on them.

Non-canon appearances

Mario is Missing

Morton is missing in both PC, NES, and SNES versions. Morton though not seen was helping Bowser taking over Antarctica. Morton however refuses to go outside or fight Luigi and is presumably watching the others.

Hotel Mario

In this game, Morton's Woodoor Hysteria was the first hotel to encounter in the game. It only takes two hits to defeat Morton and however to truly defeat Morton, Mario or Luigi has to close all of the doors to trap him.

Super Princess Peach

Morton only appeared in the beta version of Super Princess Peach. He attacks by taking mass air and inflating himself like a balloon, Spitting fireballs, charging, body slam, and diving headbutt. Not much else is known about him.


Like his brother Roy, Morton is one of the strongest Koopalings, using his weight to try and crush Mario with a powerful groundpound that causes a small earthquake that also paralyze his enemy, however Morton perfers to use his magical wand that shoots energy blast. In Super Mario World, he attacked by climbing up the walls, then he walked on the ceiling, and then, he fell on the floor, temporarily making you unable to move. When defeated, he sank into the background and disappeared in a cloud of dust.



  • He is named after singer Sean Morton Downey Junior.