The Steep Canyon

The Steep Canyon is a level found in the south side of the Music Box World in Wario Land 3. Wario can unlock this level by getting the yellow spell book and the trident which summon lighting bolts that hit the river in the south part and tear the ground to make the canyon appear.

Grey Chest : Red Gloves
To get this treasure, Wario has to make his way to the right side by breaking walls and avoiding the Fire Robotas and the water hands.The key is at the far right.

As for the chest, he has to roll from the right side of the level and avoid the Prince Froggy to break the rocks in the left side and access the Grey Chest.

The Red Gloves allows Wario to lift small enemies.

Red Chest : Conch Artifact (red)
Wario needs to get the Stone Foot which shakes the ground and fissures The Volcano's Base along with this level to manage to get this treasure. He has to enter the fissure and use the Puffy Wario form to get the red key. Then, use it again and avoid the spikes to get to the platform where the Red Chest is.

When three Conch Artifacts are collected, they cause the Volcano to erupt and make a hole in the east side named The Colossal Hole and open the path for The West Crater.

Green Chest : Telephone
To get this treasure, Wario must get the Frog Prince's Gloves from Out of the Woods. First, he has to go to the Red Key's room and fall into the water. He has to keep swimming against the currents until he reaches a warp pipe. In this room, Wario has to ground-pound the ground to make the spiky enemies float. He can use them a platforms to get to the top. He'll end up near the Green Chest. It cannot be opened however because he didn't get the key. So Wario has to enter the warp pipe near it.

Here, Wario has to use the owl to get past the spikes and the spark-like enemies, and grab the key in his way to a second warp pipe. When entered, Wario will end up in the red Key's room again. He has to do the same thing as before. Now that he has the key, the chest can be opened when he reaches it.

Getting the Telephone doesn't effect the Music Box World in any way.