Rump Command

Rump Command is a large area inside Bowser's tail in Mario & Luigi: Bowser's Inside Story. Once there, Mario and Luigi meet two Evoglobins, and the player also plays a space invaders style mini-game in which they shoot red, green, and blue orbs towards his heart to revive and make Bowser grow. However, Bowser can only grow when in peril, meaning that Mario and Luigi only need to explore here when Bowser's in danger.

This is also one of the most visited place by Mario and Luigi inside Bowser (4 times), in addition to the Arm Center.

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For some odd reason, Bowser's tail goes all the way to his kidnys. A fact of it is that when you go to the boat and leave,you can see a weird balloon thing with urine coming out. (or so i think) (Ps. sorry for mispellings)