Rumblebump Volcano is a location that is mentioned in the game Paper Mario: The Thousand-Year Door.
Rumblebump Volcano is one of many locations that was visited by Luigi in the Waffle Kingdom during his journey for the Marvelous Compass pieces. Along the way, he meets a Blooper named Blooey and the two venture inside of the volcano. The two of them encounter a large, stone guardian that Luigi manages to defeat by throwing Blooey at the monster. However, this turns out to be false as Blooey says Luigi missed the guardian completely and threw him into the lava charring him. It is unknown if the stone guardian was defeated but Luigi was able to get the piece of the Marvelous Compass.