Border Bro

The Border Bros. are the Hammer Bros. that guard the Beanbean Borderlands in Mario & Luigi: Superstar Saga. In order to pass into the Beanbean territory, Mario and Luigi must complete their game of Border Jump, which is basically jumping across a rope.

The player must avoid hitting the rope three times with either character or they will have to restart the challenge. After beating them, Mario and Luigi have the option to come back and challenge them again, but the game is harder every time the brothers beat it. Replaying Border Jump earns them more Hee Beans.

One of them wears a red flag atop his helmet while the other wears a blue one; although the Border Bros.' names are unknown, it is confirmed that the one clad in the blue-flagged helmet is the younger of them. Also, the Border Bros. seem to have known Mario and Luigi from somewhere before their encounter at the Beanbean Borderlands.

Trivia

 * The final Border Jump stage is titled Super Border Jump Sunshine, which is a reference to the GameCube game Super Mario Sunshine.
 * During the Border Bros.' first tutorial of Border Jump, if Mario jumps when they command Luigi to jump, a Border Bro will tell Mario to "give the 'Jumpman' thing a rest". This is one of the many contemporary Mario references to "Jumpman", Mario's original name used in the arcade version of Donkey Kong.
 * The poster to the back of the room depicts the ending part of a level from Super Mario Bros., and after the Mario Bros. pass a round, the poster animates and fireworks explode, just like in the game. Additionally, during the jumping game, a cover of the original theme plays.
 * The Border Bros., along with the Hammerhead Bros., and the Starshade Bros. are some of the very few characters from the Beanbean Kingdom that actually know Luigi's name. Most others just call him "Green Mario Guy" or something similar.