This article is from the 2006 series of SMBZ and is no longer canon.
Prince Morton Koopa Junior is one of Bowser's eight children and is the third youngest Koopalings. Although he is the largest of the Koopalings, Morton isn't as powerful as some of his other largest brothers, like Ludwig von Koopa or Roy Koopa, which also means his earthquakes and other brutal strength aren't powerfull than his two big brothers. This may just be due to the fact that he is one of the younger Koopalings, and needs to grow some more.
Unlike his siblings, many of Morton's features are unique, and are not shared traits. In New Super Mario Bros. Wii, his brothers and sister have their own shell colors, and as a result, the shell color is no longer unique to Morton. Also, Morton and his brother, Larry Koopa , have a star-shaped birthmark on their heads. He is also the only Koopaling to have a different skin tone rather than the yellow tone the others have, this could be because he normally rules a hot and dry area (Donut Plains in Super Mario World and Desert Land in Super Mario Bros 3).
Morton Jr. and his siblings will fight the heroes in Episode 9.