Boss Sumo Bro

Boss Sumo Bro. (or Mega Sumo Bro.) is the enlarged Sumo Bro. who first debuted in New Super Mario Bros. U. He is one of the game's mid-bosses along with Boom Boom and Kamek.

''New Super Mario Bros. U
In New Super Mario Bros. U, Boss Sumo Bro. guards his tower, Screwtop Tower, after the defeat of Boom Boom. Boss Sumo Bro. was a regular Sumo Bro. until Kamek transforms him, changing his appearance and size.

In battle, Boss Sumo Bro. jumps on every platforms of the room, stomping it to make electric waves below him in attempt to damage Mario. Stomping the ground makes Mario tremble for a few seconds. Sometimes, he stomps the floor two times.

To defeat him, Mario has to jump and hit the platform where Boss Sumo Bro. stands on, causing him to fall on his shell. While stunned, Mario has to jump on him. He has to do this three times to defeat him. Note Blocks are quite useful for this. It might impossible to stomp on his head because of his spike.

Physical Appearance
Boss Sumo Bro. has the same appearance to that of a regular Sumo Bro, except that he now wears two towels on his shoulders, his eyes aren't round, and he is larger than the average Sumo Bros.

Trivia

 * Boss Sumo Bro. is the only boss that does not appear on top of the Tower in the world map.