From the Super Mario Wiki
At Wakeport, the Bros. meet Lil' Massif who claims that the Mount Pajamaja tour cannot start unless Big Massif shows up. The Bros. eventually find Big Massif after a long trek in the Dream World, and the tour starts. Mario and Luigi eventually reach the summit of the mountain, learning some helpful moves taught to them by the Massifs along the way. The Massifs flee when they see the guardian of the summit, then decide against summiting the mountain after seeing Bowser, Antasma, and several of Bowser's minions, and are not seen again until the Mario Bros. decide to scale the mountain a second time in order to get the Pajamaja Rock Frame. The Massifs accompany them and teach Mario and Luigi the Ball Hop move on the way to the location of the bed frame. They also appear in Dreamy Mount Pajamaja as shopkeepers.
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