Last year Games Workshop celebrated Christmas with a limited-edition miniature of Da Red Gobbo dressed as Santa Claus, and this year have followed up with another promotional oddity. The Goff Rocker is a leather-clad ork with a guitar and a grenade for a microphone who looks like a cross between Lemmy from Motörhead and Slash from Guns n' Roses and has his own theme song to the tune of Jingle Bells called 'Ere We Go. (In reality it's credited to Jonathan Hartman, composer for Warhammer series like Angels of Death, Interrogator, and Hammer & Bolter.)
The Goff Rocker is a cute reference to an obscure bit of Warhammer 40,000 from 1991, when the tabletop wargame's supplement 'Ere We Go: Orks in Warhammer 40,000 presented the rules for the Goffik Rok Band. This trio of orks carrying "Rok Guitars" were the Doof Warriors of their day, playing music to keep the army pumped-up on the march. Mechanically, they got orks within 12 inches on the tabletop so excited they could shoot twice a turn, though at -1 to hit thanks to their overenthusiasm.
Back in the 1990s Games Workshop ran a record label called Warhammer Records, signing hard rock bands Wraith and D-Rok to record 40K-themed music. Prior to that the company worked with metal band Bolt Thrower, granting them a license to use 40K artwork for the cover of their album Realm of Chaos, and gave away a "flexi-disc" of thrash band Sabbat's song Blood for the Blood God with an issue of White Dwarf.
I don't imagine one Christmas novelty song marks a return to the world of rock 'n' roll for Games Workshop, but I sure wouldn't mind if it did. There's a mock tour poster for Goff Rocker's "Festive Tour M41" with special guest Sloppity Bilepiper, a reference to a daemonic Herald of Nurgle playing a grotesquely organic set of bagpipes who has appeared as a Magic: The Gathering card as well as a mini, and I'd absolutely listen to whatever music that thing produced.
Read more: Every Warhammer 40,000 game, ranked