google

        "Then what is magic for?" Prince Lir demanded wildly. "What use is
wizardry if it cannot save a unicorn?" He gripped the magician's shoulder
hard, to keep from falling.
        Schmendrick did not turn his head. With a touch of sad mockery in
his voice, he said, "That's what heroes are for."
...
        "Yes, of course," he [Prince Lir] said. "That is exactly what heroes
are for. Wizards make no difference, so they say that nothing does, but
heroes are meant to die for unicorns."
                -- Peter Beagle, "The Last Unicorn"