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Wart, as he appears in Super Mario Advance.
Wart is the main antagonist of Yume Kōjō: Doki Doki Panic, its western release Super Mario Bros. 2, and the latter's various remakes or re-releases. Wart is a green frog-like creature who hails from the dream land that is Subcon (or Muu World in Doki Doki Panic), and uses the inhabitants' Dream Machine to create monsters and wreak havoc on the world of dreams. He leads an army of monsters known as the 8 Bits.
Yume Kōjō: Doki Doki Panic
In Doki Doki Panic, Mamu seizes control of the Dream Machine that controls the weather and grants the inhabitants of Muu World peaceful dreams. Using the Dream Machine, Wart creates an army of monsters to attack the Muu, though they eventually learn of his weakness, his distaste of vegetables, and use this new knowledge to defeat the frog-like king.
The story of his uprising and defeat is told in a storybook which Rūsa the monkey gives to the two young twins Poki and Piki. During a small fight the two siblings have while reading the book, the twins tear out the last page, and make it so that Wart was never defeated by the Muu inhabitants. Wart then reaches out of the storybook and kidnaps Piki and Piki, whose cries alert the rest of their family - their parents, Mama and Papa, and their older sister and brother, Lina and Imajin - to Wart's presence, and the four of them jump into the storybook and chase after Wart.Mamu serves as the final boss of the game. One by one, he engages Papa, Mama, Imajin, and Lina in battle with the Dream Machine. During this fight, he will spit out several bubbles, which can damage the player as well as make vegetables they touch disappear. Conventional attack methods of ineffective against him; in order to defeat him, the player must throw vegetables into his mouth while it's open and spewing bubbles. After eating four vegetables, he is defeated. After his final defeat, the family frees Poki and Piki while Mamu is beaten to a pulp by the people of Muu off-screen.
Super Mario Bros. 2
Because the original sequel to Super Mario Bros., branded as Super Mario Bros.: The Lost Levels was considered too difficult for western audiences, Nintendo rebranded Doki Doki Panic into Super Mario Bros. 2, which was released outside of Japan. The world of Muu was renamed to Subcon, and Mamu gained his current name, Wart. When this game was released in Japan as Super Mario USA, Wart retained the name Mamu, though the name Subcon stayed.
Several plot elements were also changed in the transition. Like the original game, Wart uses Subcon's Dream Machine to spread mayhem and chaos in his conquest. The plot about the storybook and Wart's defeat were taken out, leaving Wart simply undefeated. Instead of fighting him, the inhabitants of Subcon, fittingly named the Subcons, enter Mario's dreams and request his help, as well as telling him his weakness against vegetables. Mario initially dismisses the dream, but he, Luigi, Princess Peach, and Toad find a door that leads to Subcon the next day, and embark on a journey to stop Wart.Wart is still the final boss, though aspects of his fight were changed as well. Instead of being battled by each character individually, he is simply battled once. He is still damaged by vegetables being thrown into his mouth while it's open, though he now must swallow six vegetables instead of four. After his defeat, while the Subcons praise Mario, Luigi, Peach, and Toad for their victory, he is seen one least time being carried by them off-screen to be beaten up by them. After this, Mario wakes up from his bed, pondering if these events really happened or if they were just a dream. He then decides to simply go back to sleep.
Wart is generally the same in re-releases and remakes of the game, though Super Mario Advance is notable for giving Wart voice acting (albeit two lines), performed by Charles Martinet, the same voice for Mario, Luigi, Wario, Waluigi, and several other characters.
BS Super Mario USA
In BS Super Mario USA, the sequel to Super Mario Bros. 2 released exclusively in Japan through the Satellaview peripheral, it is revealed that Wart escaped to another dream after his defeat at the hands of Mario and his friends. After laying low for an undisclosed amount of time, Wart and the 8 Bits return to Subcon where they force Subcon's king into hiding and steals the golden statues of Mario placed around the kingdom after Mario, Luigi, Toad, and Peach saved Subcon previously. The four of them are called to Subcon once more, this time by the king, and are asked to save them from the frog king again.
Like Mouser and Birdo, Wart will also periodically appear during gameplay to cast a spell on Mario, changing all enemies on screen into Bob-ombs or changing the character the player controls. Upon his defeat, Subcon becomes disconnected from the Mushroom Kingdom and disappears.
The Legend of Zelda: Link's AwakeningWart, under his Japanese name Mamu, makes an appearance in The Legend of Zelda: Link's Awakening. In this game, he lives in a pond beneath the Signpost Maze on Koholint Island, which is a dream land like Subcon. He isn't an antagonist in this game, and instead teaches Link a song on the ocarina called the "Frog's Song of Soul" in exchange for 300 Rupees. After this, he is not seen again for the rest of the game.
Wart appears in the very first episode of the first season of Super Mario Revival as one of the many villains revived by King Polarite. He is summoned by Emeri to fight Mario, Luigi, Peach, Daisy, and Toad.
Wart appears in Super Mario Spikers as a playable character, appearing as a Power-type Captain. Instead of wearing blue and gold, he wears red and silver. He also replaces his necklace with chains, which wrap around his body over his shoulders and under his legs. His emblem is a red, four-pointed star similar to the emblem on his usual necklace, and his theme is Highlife.
Wart appears as a playable character in Mario Kart: Infinity Remix. He is a heavyweight character, meaning that it he among the highest speed and weight stats in the game, though his acceleration and handling can dip into the lowest levels. He also has good traction and poor mini-turbo.
Wart is an unlockable character, and is unlocked randomly after winning a gold trophy on any cup on any engine class.