It's useful, up until you run out of rupees. It grants you invincibility until you run out of rupees, then it slows you down like the iron boots.

If you want to know how to get it, go to ZeldaWiki.

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Ask people about God nowadays and they usually reply, "I'm not religious, but deep down, I'm a very spiritual person." What this phrase really means is: "I'm afraid of dying, but I can't be arsed going to church."

Credit to the awesome Ranil for the sig and avatar.