Bull's-Eye Banzai

King Bills are a bright red Banzai Bill variant that only appeared in World 9-3 of New Super Mario Bros. Wii. Unlike Bull's-Eye Bill, they only have a limited homing ability where they will track their target's vertical position and then continue forward once they reach that height. Their animation is very limited as well, always maintaining a horizontal position and never turning to point at their target.

The player can defeat it by simply jumping on its head, or by running into it with a Super Star. Also, a King Bill cannot be frozen by an ice ball; it will break the ice and release itself when the ice ball reaches it. Likewise, POW Blocks are useless against them.

King Bills are never seen being fired from a Banzai Bill Cannon.

In Super Mario 3D World, another Banzai Bill variant called Cat Banzai Bill behaves similarly.

Trivia

 * King Bill is the only new enemy from New Super Mario Bros. Wii that does not return in New Super Mario Bros. U.