You need 165 gems to unlock this level.
Toadette finds herself on Flip Panel Footpath. Grab the invisible coins next to the railing and step on the switch. When you start walking on the path, a trail of smoke will follow you until it transforms into a mummified Toad who follows your every move, much like the Cosmic Clones in Super Mario Galaxy 2. The panel will take you to the lower portion of the tower with the Star. There are many coins here, so double back to get all of them. Be careful not to double back into Mummy-Me. Step on the switch when you have all of the coins. Grab the coins on the donut lifts as you follow the path. The path ends on a magic carpet with many invisible coins. Walk in a circle to get them all. Near the nearby tower are two switches. Activate the switch on the left and follow it to the ladder on the tower. Climb the ladder and grab the pickax. Turn around to attack Mummy-Me with pickax to make it disappear for a while. Pick all of the plants with the pickax to collect the coins. Drop back down to the switches. Activate the left one again and follow it to the other side of the tower for a ladder to some coins in the tower. When both switches can be pressed again, press the right switch, wait a short while, then press the left one. Follow the path on the right to some coins on some donut lifts, then transfer to the other path. Run and cut as many corners as you can, as the path will disappear quickly. Mummy-Me will be right behind you. The path will take you to the Star. If you need more coins, there are some invisible ones on the tower's outer ledge.
Special Challenge: Collect 160 coins.