Toki mentions that one of Dethklok's previous chefs had commited suicide and how it would make a good album cover. This refers to the suicide of Mayhem singer Per Yngve Ohlin. A photograph of Ohlin was taken after he had shot himself in the head, and the image was later used as the cover for the bootleg Dawn of the Black Hearts.
The fan who boasts that his eye was torn out at a Dethklok performance is the character "Goat" from Megas XLR and Downtown.
While using the supermarket microphone, Nathan makes reference to the Cannibal Corpse songs "Every Bone Broken", "Rotted Body Landslide", and "Hammer Smashed Face".
An Adult Swim bump, written in response to an email asking if the song 'Mermaider' was about mermaids that murdered or mermaids that were murdered, explained that 'Mermaider' "happens to be about homicidal mermaids that have murdered thousands of yellowtail tuna, and later tragically get murdered by a group of bi-polar octopi."
Near the beginning of the Thunderhorse video, Dick "Magic Ears" Knubbler's head can be seen impaled on a pike.
"Birthdayface" (a.k.a. "Happy Dethday")
On the Adult Swim Fix, this episode was billed as "Birthdayface".
Goat makes a guest appearance as a member of the audience during the demolition derby.
Metallica guitarist Kirk Hammett provides the high-pitched voice of the Queen of Denmark.
For a birthday present, Murderface receives a new car, complete with metal accessories. As the band is admiring it, Toki quotes, "Big fat tires and everything!", a reference to the Deep Purple song "Highway Star".
When the Rock n' Roll clown is performing for Murderface, he makes a balloon replica of Bootsy Collins' famous space bass.
It is revealed that neither Toki nor Skwisgaar knows how to read music and that they usually resort to the "old music school trick" of playing random notes.
There is also a reference made to the band Children of Bodom at the end of the episode, when the band's hometown of Espoo, Finland is seen on fire and in ruins. The lake from which said troll was summoned may also be a reference to Lake Bodom - the location of the murders from which the band derived its name.
Nathan Explosion's quick speech before the band performs "Awaken Mustakrakish" as an apology to the Finnish people is a reference to the Finnish band Amorphis who took much of their lyrics from their albums 'Tales From The Thousand Lakes' and 'Elegy' from actual ancient Finnish texts.
First appearance of the 'Dethphones' used throughout the series.
The hearing that opens the episode is a reference to the Judas Priest "Subliminal Suicide" trial of the 1980's in which alleged backwards-masked lyrics drove a youth to "try suicide," and to "do it, do it."
During the sequence in which the band's comedic success is represented by a series of newspapers and magazine covers, a magazine called "Donkey Punch" is shown, referring to a sexual technique.
The newspapers covering Dethklok were USA Mouth, Your Liberal Lip, and The New York Chronicle. These parodied USA Today, The New York Post, and The New York Times, respectively. In addition to those written about Dethklok, other articles included "Rich Idiot Still a Complete Moron at 57", "Is Rap Metal Finally Dead? Yes, It Is," and "Panda Power Twins Lose Big." Senator Stampingston could also be seen on the The New York Chronicle.
Nathan's "twin" Kuato is a reference to the telepathic mutant rebel leader Kuato from the movie Total Recall.
The titles of various stores shown throughout the episode reference several true black metal bands, including Burzum, Gorgoroth, and Marduk.
Murderface says "I'd rather be sanded faceless than grow old and repugnant like that." This line is a reference to the Cannibal Corpse song, Sanded Faceless.
During the closing credits, Murderface's grandfather says through his speech synthesizer "kill me", over and over again. This is a reference to a line from the film Johnny Got His Gun which was sampled in the video for the Metallica song "One".
The beginning of this episode takes place in Machaerus, Jordan. Machaerus is a fortress fifteen miles southeast of the mouth of the Jordan river, in the wild and desolate hills that overlook the Dead Sea from the east. Known today as Mukawir, this dramatic hilltop is the traditional site of the execution of John the Baptist.
In one scene, Toki gives himself a solid gold telephone. "Solid Gold Telephone" is a song by Head Automatica.
The end of the episode is a refrence to the music video of the song "Du Riechst So Gut" by Rammstein in which the band members have red eyes and turn into wolves.
"Snakes 'n' Barrels"
Goat has another guest appearance as an audience member at the Snakes 'n' Barrels reunion concert.
The Snakes 'n' Barrels song "Water Horsey Blues" is a parody of Guns 'n' Roses "Garden of Eden".
At the end of the credits, the bassist for Snakes 'n' Barrels repeats "I'm a chicken" several times, in reference to an early health film distributed by the government on the dangers of LSD where a teenager believed he was a chicken after taking LSD.
After the "Weeks Later" bump, The music video for Crush My Battle Opponents Balls shows the video director being King Robot, a name for Jon Schnepp, co-producer of the show and editor on Space Ghost Coast to Coast.
Jon Schnepp makes a voiced appearance as the director of Skwisgaar's video shoot, and has his cranium sliced off when the dragon puppet malfunctions.
The Skwisgaar Skwigelf Advanced Fast Hand Finger Wizard Master Class is a reference to a short film by Brendon Small featured on the Home Movies first season DVD boxset, entitled The Thor Von Clemson Advanced Fast Hand Finger Wizard Master Class.
"Murdering Outside the Box"
The Council's spy strikes a Mordhaus guard in the head with a hammer, referencing the Cannibal Corpse song "Hammer Smashed Face".
The motivational speaker also references the song "Hammer Smashed Face" in his speech.
Agent 2-16 rises headfirst from a pool of water in a scene similar to a well-known sequence in Apocalypse Now.
The motivational speaker's exaggerated running and screaming on stage is a parody of Microsoft CEO Steve Balmer jumping and screaming while hosting a Microsoft employee convention.
This is the second episode in the series to feature a scene depicting the deaths of the entire band (except for Nathan Explosion). The first was in Dethwater, where the deaths were part of a music video for Thunderhorse.
Nathan Explosion takes his GED test at Carpathian Forest High, a reference to the Norwegian black metal band Carpathian Forest.
William Murderface's inability to spell could be a reference to Ozzy Osbourne's dyslexic nature.
Juliette Sarmansadandle is seen pretending to play a guitar from the game Guitar Hero. The Dethklok song Thunderhorse appears in Guitar Hero II
Toki's outfit in this episode (with the ridiculously spiked wristbands and shin guards) is in the vein of outfits worn by black metal bands like Satyricon.