The Super Bell can be used by Mario, Luigi, Toad, Rosalina, Bowser, Toadette and Peach. The user of it gains a Cat costume and has the ability to climb up walls. Also while in Cat Form, the user can perform a swipe attack, rather than knock enemies over, and a diving attack to usually defeat them in one hit. When Bowser uses a Super Bell, he becomes Meowser.
The Super Bell transforms the player into a Cat form. Thus the name Cat Mario originated (Cat Luigi, Peach, Toad, etc.)