Level 3-8 (Mario vs. Donkey Kong: Tipping Stars)
From the Super Mario Wiki
The course is composed of several floors with a series of Ladders and Purple Conveyor Rivets. A gray conveyor is present as well. After initiation, the Cursed Mini Mario climbs up a Ladder, falls into a gap, and turns around due to a conveyor moving in the opposite direction. The other Mini toys start on different floors. One of them should be lured to grab a pair of Hammers in the center of the stage, then brought into the Cursed Mini Mario to revert it to a normal Mini Mario. Afterwards, all Minis should be led to the Goal Door in the bottom right corner of the course.
The M Coin is on a platform right above Cursed Mini Mario's starting position, between the leftmost Ladder and the Hammers.
Nintendo 3DS version
Wii U version