Instructions
Dig down through the ground you land on using the "Triangle" button on PlayStation 2 or the "C" button on the Wii.
Go to the right when you reach the first spike block before digging down again.
Go right as far you can and then dig down until you reach the black blocks.
Head to the left until you spot the waterhole beneath you. Stop one block to the right of it, dig down one, and then jump out before standing over the waterhole again. Dig down and drop into the water.
Get out of the waterhole to the left. Go to the left as far as you can and dig down through three blocks.
Go to the right as far as you can. Dig down until you reach the bedrock. Watch as Kaguya automatically comes to a stop over a block. Dig down into the block and you will exit the spiky stone level.