In any era of music, the cover song has remained a staple, and with five decades of heavy metal to work with, we've selected The Best Cover Songs From 50 of Metal's Biggest Bands.

In decades long gone, the cover song was the most optimal way for a band to launch their career, and it wasn't uncommon that a group would cover a track that had only been released within the last year or two. Tackling an already successful hit was an easy way for a new band to slip into radio rotation and get some exposure on the airwaves before listeners were ready to hear an original from these emerging artists.

Even today, that path to initial success remains an option, only now it has become sort of a viral sensation with dozens of metal artists covering mainstream hits either with utmost sincerity or a complete piss-take "for the lulz."

Then there's just the plain fact that bands want to play some of their favorite and most influential songs from growing up and learning as a musician. Whether it's a faithful recreation of the original or a full-on stylistic reboot, the cover song is never without intrigue.

In the list below, some of the selections are no-brainers while others are steeped in controversy. So let's get started... Oh, and if you're looking for The Best Cover Songs by 40 of Rock's Biggest Bands, you can find that here.

The Best Cover Songs From 50 of Metal's Biggest Bands