Metal/Hard Rock bands you regret not seeing/Bucket List Bands

Some years back, Andrew WK hosted a kids' game show on Cartoon Network (!) that my sons watched. I forget what it was called, but they had two teams of kids who had to assemble a machine using random crap from a junkyard, then the machines would battle each other. At the end of each show, the loser's machine was blown up by the winning team.   It was a lot of fun, I remember my kids were surprised that I knew who Andrew W.K. was.

*EDIT* The show was called "Destroy, Build, Destroy."

OK I had to look it up. 

You guys were talking like Andrew WK had passed on.  I love his simplistic style of party anthems (like the "I Get Wet" album) and I was bummed when I thought he was dead.  Thankfully he's not.  At least not according to Wikipedia.

Van Halen - I've seen David Lee Roth and Sammy Hagar both as solo artists. But never VH.

Death - I could have seen them on the Human tour and for whatever dumb reason I passed.