Mountain is World 10-3 in Story Mode in Super Monkey Ball 2.
A mountain with a flat circular top spins counterclockwise. A bridge connects the starting platform to the top of the mountain. There are several cone-shaped protrusions near the base of the mountain. A banana bunch is on the top of the mountain. The goal is at the base.
There is only one goal, the blue goal. Roll onto the top of the mountain. When you see the goal, roll down the side of the mountain, and stay to the left of the goal. If you time it right, the goal should catch up to you by the time you are about to roll off the bottom.