Some sample lines:
"C'mon Kage, bring the thunder!" (Beelzeboss)
"We've walked with Jesus and his Cross. He did not die in vain!" (History)
"Kyle's fingers be silver. Jack's voice then be gold. But lest you think we're vain..." (History)
"Look into the Sasquatch Eye. Then you know that Sass can fly. Sasquatch is my daddy and he's going to protect me." (Papagenu)
"Our tasty grooves are better than chicken chow mein" (P.O.D.)
What I find funny about Tenacious D is that they're kind of an unabashedly crappy metal band that celebrates the shallow and idiotic details of heavy metal. The lyrics are usually a mix of fantasy (dragons and wizards), partying (smoking weed and rocking people's socks off) and the mundane (fast food and the rent), often all in the same song. I also think it's hilarious that the lyrics sound so extemporaneous, like Jack Black was just singing off the top of his head.
This album seems less pot-fueled than the first, which at times had a certain "Dave's not here, man"-quality to it.
It's all incredibly stupid but hard not to like.
Also, Dio and Meatloaf make guest appearances on the song "Kickapoo."