Boss Sumo Bro
From the Super Mario Wiki
Boss Sumo Bro is an enlarged Sumo Brother who appears in New Super Mario Bros. U and New Super Luigi U. He is one of the game's mid-bosses along with Boom Boom and Kamek. He appears to wear two tsuna around his shoulders, the ceremonial rope typically worn by yokozuna sumo wrestlers around their waists.
New Super Mario Bros. U
In New Super Mario Bros. U, the Boss Sumo Bro awaits in his tower located in Rock-Candy Mines after the defeat of Boom Boom. Boss Sumo Bro was a regular Sumo Brother until Kamek transforms him, somewhat changing his appearance and greatly increasing his size. He is battled in Screwtop Tower.
In battle, Boss Sumo Bro jumps between the platforms in the room, stomping them to make electric waves below him in attempt to damage the player. Stomping the ground makes it shake for a few seconds, which may stun the player. Sometimes, he stomps the floor twice.
To defeat him, the player has to jump and hit the platform where Boss Sumo Bro stands, causing him to fall on the back of his shell. While Boss Sumo Bro is stunned, the player must jump on him. He or she must to do this three times to defeat him. The Jump Blocks in the room are quite useful for this because it is impossible to stomp on his head because of the spike.
New Super Luigi U
The boss has the same appearance to that of a regular Sumo Bro, except that he wears two towels on his shoulders, his eyes appeared to be dash-like and slanted, and he is larger than the average Sumo Bro.
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