Ah, this brings back memories...
I hated fighting Cortez, he was the only boss who actually killed me (Shadow Queen only got me to 20, Bonetail made me use a Life Shroom). His 4 forms really ticked me off. And now I have to redo him because my memory card got formatted, bleh.
But aside from that, good song, pretty catchy, although it tends to get a bit boring since it seems to repeat itself.