When Nathan Explosion yells over the loudspeaker at the grocery store, he makes references to three different Cannibal Corpse songs: "Rotted Body Landslide," "Every Bone Broken," and "Hammer Smashed Face."
Dethklok play Gibson Guitars and Krank Amps exclusively. William Murderface plays a Gibson Thunderbird Studio 5-String Bass. Skwisgaar Skwigelf plays a Gibson X-Plorer (Explorer) guitar. Toki Wartooth plays a Gibson V-Factor (Flying V) guitar.
When Dethklok talks about "blowing your brains out" would make a great album cover, they are referring to Norwegian black metal-band Mayhem's "Dawn of the Black Hearts" bootleg album. The cover artwork is a photo of band member "Dead" after he committed suicide in 1991, using a shotgun to his head.
Members of San Francisco metal band Metallica, James Hetfield and Kirk Hammett voiced Fan #1 and Fan #2 in the episode "Curse of D." Michael Amott of Swedish metal band Arch Enemy has also lent his voice to a future episode, as have members of Seattle metal band Nevermore.
According to a behind the scenes video on AdultSwim.com, all guitar parts played by Dethklok are fret-accurate reproductions of Brandon Small's guitar playing. Originally Small had played the parts in front of a green screen and had sensors attached to his fingers for the animators to reproduce, but this way was scrapped in favor of the animators referencing video and photos to traditionally animate the guitar playing.