Any song with pulse shattering vocals and face melting guitar solos. This type of song will never be heard on the radio as the general public couldn't possibly comprehend all its majesty and splendor. Songs of this magnitude are more scarce than a seal in a shark tank. So don't go naming every Nickeback single you hear epic. In fact if you listen to nickelback an epic song would break you.
Iron Maidens Number of the Beast! This little hell raiser from the 80s Is a massively epic song. Listen at your own risk and keep it away from women, children, and babie kittens.