UPDATE: As you may have heard, this album and band were made up by Phish, and the tracks played by the band during last night’s second set were, in fact, new original tunes, á la Phish’s 2014 Halloween re-imagining of Disney’s Chilling, Thrilling Sounds of the Haunted House. Read our full recap of the show here.

Phish have delivered yet another curveball to their fans, as revealed in the official Phishbill given out before their Halloween show on Wednesday night in Las Vegas: The band has opted to cover an obscure record entitled í rokk by Scandinavian band Kasvot Växt.

Not much can be found online about the band or the album—leading some fans on social media to initially wonder if Phish had made them up—though some savvy searchers soon uncovered a couple of sources that seem to verify the band’s existence, including this 2005 blog post from New Jersey’s WFMU radio station and this 2006 interview with the members of Kasvot Växt (although to be clear, the references to the group on Allmusic appear to have been created within the past hour so there will be plenty of healthy skepticism until the first notes of the second set. Indeed, the first sentence of the Phishbill essay introducing the album reads, “It is as if Kasvot Växt never existed…”).

The group has also shared the official Phishbill in a full PDF, viewable here, which gives more information, including the fact that the album came out in 1981, it was Kasvot Växt’s only released record, and there is a lot of mystery surrounding the group. The translations of the band name and album title are Faceplant and into rock, respectively, while some of the translations of the album’s track titles include “Turtle in the Clouds,” “We Are Come to Outlive Our Brains” and “Death Don’t Hurt Very Long,” with the lyrics switching from Icelandic to Finnish to Norwegian.

Much more from the band’s investigation is detailed in the Phishbill’s article, but the key seems to comes at the end of the piece, with drummer Jon Fishman summing it up: “So what can Phish fans expect? A weird, funky Norwegian dance album! Get out there and put your down on it!”