Johnson (Super Paper Mario)
From the Super Mario Wiki
While the Hammer Bro Captain is trying to free the Koopa Troop, he encounters Johnson and another Koopa Troopa. They try to convince him to convert to Count Bleck's side, and the Captain resists until Nastasia shows up and hypnotizes him. Nastasia then orders the captain to catch the rest of the unhypnotized minions, and he, Johnson, and the other Koopa Troopa head off to do so.
The two then help chase down Peach, and they catch her on a ledge outside the castle, but she is teleported to safety at the last minute by Dimentio. Very little is known about Johnson, and it is unknown if he appears again, as he looks like an average Koopa, meaning it is also impossible to discern him from the rest of the crowd present at Bowser and Princess Peach's wedding, as well as any other Koopa Troopa that appears in the game.
It is presumed his mind was changed back after the ending of the game.