The Koopa Bros. are a team of bosses that appear in Paper Mario. They are Koopas that wear ninja garb and hold onto one of the Star Spirits, Eldstar, for Bowser. It is said that the Koopa Bros. once lived in Koopa Village, a town of reformed Koopas. They later moved to a castle the Bob-ombs lived in and enslaved them. Eventually, Mario, with the help of Goombario, Kooper, and Bombette, saved the Bob-ombs and defeated the Koopa Bros. After their defeat, they send a letter to Mario, vowing their revenge. Before the final battle with Jr. Troopa in Chapter 8, the Koopa Bros. appear and tell Mario that they were nothing than before.