New Super Mario Bros. U Blind Walkthrough Part 24: Light The Way

That dark stage was pretty neat! The hidden areas give you the feel of traveling outside on small ledges outside the mountain.

-Time Stamps-

0:00 Rock-Candy Mines-3 - Waddlewing's Nest
4:13 Rock-Candy Mines-Life House
5:25 Rock-Candy Mines-4 - Light Blocks, Dark Tower

Enjoy!