King Bill

King Bills are a new sub-species of Bullet Bill that so far have only appeared in the last level of New Super Mario Bros. Wii, in World 9-8. King Bills are invincible, being unable to be beaten through any maneuver or item, and only avoided through outrunning and reaching the end-level flagpole. Like Banzai Bills in Super Mario World, King Bill Blaster isn't seen.

It's very large in size, taking up nearly the entire screen, which makes it much larger than the previous biggest Bill, Banzai Bill. It is the biggest non-boss enemy of the game, being beaten out by Bowser's giant form after Kamek's spell in Bowser's Castle.

There are a total of 10 King Bills in New Super Mario Bros. Wii.