Secret Bonus Area #55 in The Mushroom ShoreEdit

SBA 55

The 55th Secret Bonus Area can be accessed by finding the entrance in The Mushroom Shore

The entrance is located at the top right of the zone[North of field 3]. It can be accessed as soon as you clear the blockade and can enter field 3. Find a small gap between the trees in the top right of the zone and follow the partially hidden path into the SBA.

The puzzle has 81 Puzzle Piece

After completing the puzzle you will be rewarded with a Codename Banner ranch decoration item.
Codename Banner MushroomZone