This page explains how to find the Rucco Maag shrine and solve the "Five Flames" puzzle.
Location of the Shrine
After you activate Lanayru Tower, make your way east along the road toward Zora's Domain. When you reach Ruto Mountain, look south across the Rutala River to see the Rucco Maag Shrine.
Alternatively, you can go east from Mezza Lo Shrine to find this shrine.
How to Reach the Shrine
The shrine itself is surrounded by a maze made of stone spikes. These spikes can't be destroyed, and they are in tall grass, so make your way slowly. You will also have to get past some Lizalfos in the surrounding area.
Your goal is to light all of the five torches on the floating cube and the two pillars beside the cube, but beware that the water spout on the big cube will extinguish torches, and pointing a torch underwater will extinguish it as well.
Hit the crystal on the bottom of the small cube. Then use your bow to shoot the crystal that is farthest away from the big floating cube, then shoot that same crystal again.
Next, shoot the crystal on the left side of the cube. The water spout should now be pointing underwater. Then just shoot the crystal that is farthest away from the big floating cube, and keep shooting that same one until all five torches are lit.
Before you talk to Rucco Maag and get the Spirit Orb, there are two chests on wooden ledges in the back of the room. Shoot the platforms with fire arrows to make the chests fall. You can shoot regular arrows through the torches on the floating cube if you prefer. The chests contain an opal and a Silver Bow.