From the Super Mario Wiki
“Listen up, gang! These guys are gonna put a stop to OUR party! Are we HAPPY about this?!”
Mack is a lieutenant of the Smithy Gang and the boss of the first chapter of Super Mario RPG: Legend of the Seven Stars. Mack commands an army of Shysters and can use fire magic. Like the other members of the Smithy Gang, Mack is modeled after a weapon (in his case, a knife) and he is named after the song "Mack the Knife" (originally "Die Moritat von Mackie Messer" in German).
With his Shysters, Mack attacked the Mushroom Kingdom while Mario was in Bandit's Way. Mack occupied the throne room of the Mushroom Castle while his Shyster terrorized the residents of the surrounding town.
At the start of the battle, Mack is accompanied by a quartet of Shysters Bodyguards. If they're not defeated within one turn, Mack will jump out of the battle screen and will not return until all bodyguards on the field are defeated. When in battle, Mack attacks with physical strikes and the spells Flame and Flame Wall. After a few turns, the Shysters will return, requiring the player to repeat the process until Mack is defeated.
Mack is a red-colored, roundish figure who holds onto a pair of handles on top of a giant knife with floating eyes (or may be the knife itself), mirroring how the Shysters and their derivatives ride on pogo sticks. When attacking, Mack shakes his head.
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