A Boss Bass is a larger type of carnivorous Cheep Cheep found in several games especially during the GameCube Era. They debuted in Super Mario Bros. 3 and since then have been terrorizing the waters of the Mushroom Kingdom eating anyone or anything that stands (or swims) in their way. They have been recurring enemies in the Yoshi series.
The Boss Bass appears in Yoshi's Island DS where it is found in several levels of World 3 patrolling the surfaces of the waters. Whenever Yoshi comes near, they leap in the air and attempt to eat him. If Yoshi is underneath the Boss Bass' mouth as it descends, he and the baby will be eaten. The Boss Bass either stomps or bobs in the water before making it's leap. Boss Bass' cannot be defeated by any means but tossing an egg at one will get it in the Island Museum. The leader of the Boss Bass' Bessie Bass also appears in this game as a mini boss.
- The female counterpart of a Boss Bass is a Big Bertha.
- The Boss Bass resembles the Cheep Chomp, another large carnivorous Cheep-Cheep except the Cheep Chomp is purple and lacks the menacing grin the Boss Bass has.