This season featured guest voice actors from musicians such as Kirk Hammett of Metallica, Slash, Scott Ian of Anthrax, Joe Satriani, Steve Vai, Ace Frehley, Matt Pike of High on Fire, Dave Grohl of Foo Fighters; Brann Dailor, Brent Hinds, and Troy Sanders of Mastodon; and Grutle Kjellson, Arve Isdal, and Herbrand Larsen of Enslaved.

Mordhaus is now a floating fortress and is undergoing heavy renovations to repair the damage from the Revengencers attack, but due to the band's inability to manage their finances they find themselves in a financial crisis.

But their plans run afoul as their record label's president falls gravely ill, and his son (voiced by Steve Vai) is put in charge, and wishes revenge for an incident at the beginning of Dethklok's career.

The concert begins as planned, but the plug is literally pulled on Dethklok, and are unable to continue unless they renegotiate their contract on terms much more favorable to the label.

Trying to distance themselves from celebrity status and re-connect with normal people, Dethklok decides to join Thunderhorse, in the process kicking out all the original members.

Guest voices: Slash, Scott Ian of Anthrax, Laraine Newman, Steve Vai After a near-death experience, Dethklok must face the brutality of going to a doctor.

Guest voice: Ace Frehley As Murderface and Knubbler prepare for their upcoming Christmas special (funded by the Christian church), Dethklok's mothers arrive for the festive season.

He, the drunk moms and Dethklok crash the Christmas special and the credits roll as Toki gets crushed by a large, wooden cross as Stella knocks it over while drinking alcohol, Rockso gets a handjob from Serveta and Murderface gets brutally beaten by the head of the Christian church in front of a studio audience and live broadcast.

Guest voices: Grutle Kjellson, Arve Isdal and Herbrand Larsen of Enslaved, Laraine Newman After many paternity lawsuits, Skwisgaar decides that he should find his father.

While Toki and Murderface learn the horrors of managing the entitled and abusive band, Pickles, Nathan, and Skwisgaar are unhappy with their new 47 songs because they lack the negativity normally instilled by the two suspended bandmates.

While in rehab, the band replaces Pickles at practice with a high tech, sentient drum machine named X2P1158 which is inexplicably armed with a 10,000 megaton self-detonation device.

At the rehab center, Malevolent Creation, Pickles tries to escape, but is stopped, eventually admitting that his alcoholism began when his brother, Seth, blamed him for burning down the family garage as a child.

Guest voice: Kirk Hammett of Metallica Toki tries to reunite Dr. Rockso's band, and make his life more successful by investing into the ultimate Zazz Blammymatazz reunion.

It is revealed that this is at least the 4th attempt to reunite Zazz Blammymatazz, and the other reunion concerts were canceled for a multitude of reasons, usually revolving around Rockso's drug addictions.

As part of Dethklok's attempts to promote the reunion concert, Dr. Rockso's past is revealed, his fall from grace having been caused by a love affair with a 14-year-old girl named Dory McLean in 1981.

Rockso attempts suicide by snorting a powerful drug, but the band manages to find and revive the clown, and his return coincides with Toki coming to terms with his abusive childhood.

Growing annoyed with Offdensen's neglecting them in favor of work, Dethklok unwittingly double-books a gig in both Israel and Syria, putting the two countries at risk of starting a war.

Dethklok perform using Offdensen's plan to use 3D holograms, appearing at both concerts and averting the war, which ultimately brings about peace in the Middle East.