He is a young African American child who wears red king clothing and a giant red crown
Like most children in power King Mamood is selfish, spoiled, bratty and does care who he hurts to gets what he wants however at the end of the episode he is shown to be more caring and what to help his people.
His emotions are linked to the land of Quirkistan, so whenever he is happy the land is prosperous but when he is upset the land becomes a barren wasteland. It is unknown if he possesses other forms of magic or will when he grows older.
Role in the episode
A spoiled, kid king named King Mamood tells his assistant, Wazeer, that there's a speck in his royal milk. Wazeer tells him that it's just a little speck and King Mamood gets angry, which makes the weather even worse. So Wazeer is about to get him another glass of milk.
Back to the gang, Carpet rescues Aladdin and they all go to the palace to fulfill their diplomatic mission. Wazeer tells everyone that when Mamood is happy, the weather is beautiful, but when he's angry, the weather is bad. He shows them a treasure that he will give them if they make the king happy. Everyone tries to make Mamood happy, but instead he gets bored until Aladdin juggles many swords and the weather becomes nice. But then, Aladdin accidentally pins Mamood with the swords. The king gets angry and the weather becomes bad again. Mamood now wants the gang to leave, but then Jasmine gets an idea. She tells Mamood a story about how a golden prince met the king of the genies. The story makes Mamood happy and the weather becomes nice again.
Wazeer then suggests they keep Jasmine forever, but everyone refuses to accept that and they try to escape, making Mamood angry and the weather is getting really bad. After the gang escapes the palace and land somewhere in Quarkistan due to a volcano erupting, they run into a mob of villagers, who blame Jasmine for making Mamood angry. But then, one of the villagers tells everyone that it's not really Jasmine's fault and then Mamood shows up on a winged horse and takes Jasmine.
At night, depressed, Aladdin gets an idea after Genie mentions that Mamood doesn't know how miserable he's making everybody. They go to the palace and Aladdin and Jasmine miserably say goodbye to each other. Genie turns Iago and Abu into Jasmine's "parents" so they can say goodbye to her as well. Genie then turns himself into everyone else who will miss Jasmine: Jasmine's "grandfather", a couple of village orphans, and her "pet wallaby" named Edgar. Mamood becomes depressed and it starts raining as he begins to cry. He then becomes happy for doing something good for other people and the weather becomes nice again. The king then decides to do more good stuff. Aladdin and Jasmine can now be together forever.
He and Wazeer attend Aladdin and Jasmine's wedding as seen in a cameo at the very end of Aladdin and the King of Thieves film.