Mandibug Stack

The Mandibug Stack is a pair of enemies appearing in Super Mario Galaxy and its sequel. It consists of a large Mandibug with a smaller Mandibug on its back. It appears in Super Mario Galaxy in the Honeyhive Galaxy mission "Trouble on the Tower", and Super Mario Galaxy in the Puzzle Plank Galaxy mission "The Puzzling Picture Block" (after the puzzle on the final planet is solved), serving as a sort of mini-boss in both games. To defeat the Mandibug Stack, Mario or Luigi must first defeat the smaller Mandibug on top with a Ground Pound. Upon doing so, the larger Mandibug will become angry and approach Mario faster than a regular Mandibug. Defeating the larger one reveals the Power Star.

Trivia

 * The Mandibug Stack in Super Mario Galaxy 2 has Giga Lakitu's boss theme.