While it might seem like the 'That Metal Show' has attracted a veritable Who's Who of metal artists over the course of the past six seasons, host Eddie Trunk has revealed that there are a few 'Holy Grail' guests who haven't yet appeared on the show.

"For me on a personal level, [it would be ] British band UFO," Trunk recently told Noisecreep. "They [would] benefit more than any band, since they've never been on [the show] and I talk about [UFO] so much that people goof on me! But mainstream-wise, we've never had Gene [Simmons] or Paul [Stanley] of KISS, or Ozzy. They have passed on doing the show, perhaps for some issues we're not fully aware of. We invite them every season, but they choose not do the show."

Trunk says he isn't sure why these mammoth acts have declined to appear on the show. "We can't read their minds. We are honest," he said. "If we don't like it, we say it, and that tweaks people. Maybe we said something they didn't like. They can come on to discuss it with us. A lot of times this can be a case of you didn't say it, but of them thinking you said it. Hopefully, they come around and cave. We're only fans and we say, 'Come debate it with us.' Tons of artists have and it makes the show fun."

As for the show's infamous Stump the Trunk segment, Trunk said that a hard trivia question is one that is "multi-tiered and it's not just one answer. When it's a three-parter, I am like, 'Wait a minute.' One area that I am bad at is dates! I don't remember my own family's birthdays!"

'That Metal Show,' which tapes several shows in a matter of days, now features Billy Sheehan [Mr. Big, Steve Vai] playing bass into the commercial breaks. The show is also welcoming return guests for the first time in the show's history.

Guests for this season of 'That Metal Show' on VH1 Classic:

3/19 – Kirk Hammett (Metallica) and Uli John Roth (Scorpions)

3/26 – Ace Frehley (KISS) and Billy Sheehan (UFO, David Lee Roth)

4/02 – David Coverdale (Whitesnake, Deep Purple) and Lita Ford (The Runaways)

4/09 – Chris Jericho (Fozzy, WWF Wrestling Champion) and Yngwie Malmsteen (Alcatrazz, Steeler, Rising Force)

4/16 –Duff McKagan (Guns N' Roses, Velvet Revolver, Jane's Addiction) and Glenn Hughes (Deep Purple, Black Country Communion)

4/23 – Matt Sorum (Guns N' Roses) & Cherie Currie (The Runaways) and Jim Norton (comedian on Opie and Anthony and Howard Stern)

4/30 – Sebastian Bach (Skid Row) and Anvil

5/07 – Carmine Appice (Vanilla Fudge, Ozzy Osbourne Band, Beck Bogert Appice, Rod Stewart) and Dave Meniketti from Y&T

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