This page offers a guide on how to get the hidden star Bullet Bill on Your Back. This hidden star is obtainable during the Sunbaked Sand Castle level. This level is found in the Dusty Dunes Galaxy.
The Rising Planet
When you land on the first planet you’ll need to ground pound the button, which will cause the planet to rise past the Brick Blocks which can crush you if you get trapped underneath. When you reach the top take the Launch Star to the next planet.
Hidden Star Chips in the Hidden Tower
Ground pound the button to make the tower rise from the sand. The Star Chips will be placed in various locations around the tower and can be easily seen. After you collect all five pieces a Launch Star will appear and will transport you to the planet with rising and falling sand levels.
Low Tide Secrets
Normally when you land on this planet, you need to defeat the Big Thorny Flower to reveal a Launch Star. However, this time you need to do things differently. When the sands levels are at their lowest, the planet should reveal a wooden stump that you need to ground pound. This causes music notes to appear and you need to collect and follow them. Once you have collected them all, a Launch Star will appear to take you to a new area.
Buried and Caged Power Star
When you land on the new planet you’ll be met with a turret that can shoot Bullet Bills from either side. To reveal the location of the star you need to press the blue button. This will cause a tower to rise under the turret and large number of Dry Bones appearing along with three cages. You will see Star Bits in one cage, a Rainbow Star in another and of course the Power Star in the last cage.
You will need to get the Bullet Bills to lock onto you and chase you so you can direct them to blowing up the cages. If you need to lower the tower you can press the red button, that is easily seen on the planet. However, this will submerge the cages again.
When you break the cage the Power Star will set itself on top of the tower so you need to bring the tower back down by pressing the red button. Then the Power Star will be yours for taking!