Check out the songs that 30 huge rock and metal bands have only played live once.

It's a pretty unique occurrence and one that invites loads of questions. We all understand that some songs — particularly new ones — may only ever be played live on the supporting tour. That's a rarity in itself, but to only ever play a song one time onstage? It doesn't make a ton of sense.

Even if the crowd doesn't react or the band feels there's something off, only ever giving a song one shot onstage almost feels criminal. Especially when one of those songs is AC/DC's "Big Balls." In fact, AC/DC have a lot of songs they've only performed once!

READ MORE: 50 Best Metal Album Openers of the 1980s - Ranked

Metallica, meanwhile, only have a small handful of songs that they've played live just one time. They're known for constantly switching up their setlists and digging up deep cuts, so you never know when one of those may see the stage again.

Below, you'll find the rarest of the rare live tracks from Slipknot, Halestorm, AC/DC, Metallica, Iron Maiden, Blink-182, Foo Fighters, Korn, Red Hot Chili Peppers and so many more!

The Songs 30 Huge Rock + Metal Bands Only Played Live Once

Note: songs that were played as part of a medley and cover songs were not considered for this list. Only full performances of individual songs were taken into account.

Gallery Credit: Joe DiVita

Most Played Cover Songs By 50 Big Hard Rock + Metal Bands

We combed though setlists of the biggest names in rock and metal to find out their most played cover songs. (OK, so we actually used Setlist.fm. What, did you think we had a pile of setlists sitting around?)

Gallery Credit: Rob Carroll

More From KLAQ El Paso