Ninji

Ninji are small creatures that first appeared in Super Mario Bros 2. One variety hops vertically, the other hops and moves toward Mario. There is also a giant variety with the same attack pattern. In their initial appearance, they had to be picked up and tossed to be defeated. In their next appearance in the final level of Super Mario World, a stomp will do. Since then, they have appeared in Paper Mario games and others.