Warhammer 40,000 is one of the most comically over-the-top dystopias in all of science fiction. It's a weird and wonderful world whose "heroes" don't hesitate to end billions of lives to catch one villain, a sclerotic vision of the future in which the human race is enslaved by the psychic corpse of its defeated god-emperor. It's so miserable that its slogan—"In the grim darkness of the far future there is only war"—inspired the "grimdark" sci-fi genre.

This week, however, it's somehow got even worse.

PETA—the animal rights group famed for its ridiculous stunts, and asserting monkeys can own intellectual property—has set its sights on Games Workshop's universe, by writing an open letter to its CEO asking him to "consider removing fur garments from your Warhammer characters at the next opportunity."

Numerous Games Workshop characters wear furs across both its science fiction and fantasy worlds, not least the Space Wolves, its range of Viking-inspired space marines who tend to drape themselves in the pelts of alien wolves.

"These battle-hardened warriors are known for their martial prowess—but wearing the skins of dead animals doesn't take any skill," wrote PETA's Yvonne Taylor.

"And while we appreciate that these are fictional characters, draping them in what looks to be a replica of a dead animal sends the message that wearing fur is acceptable—when, in fact, it has no more place in 2017 than it would in the year 40,000."

Many fans have taken umbrage with one of PETA's assertions—that "nothing on the bloody battlefields of Warhammer’s war-torn world could match the horrific reality" that animals suffer in the fur trade. This claim is manifestly untrue: Warhammer 40,000 is one of the most unrepentantly vicious science fiction creations in human history, with the space demons of Event Horizon rubbing shoulders with the fauna of Alien, and humanity ruled by a malevolent galactic Spanish Inquisition. The fur trade is honestly the least of anyone's woes.

PETA tried going after the nerds once before in 2011 when it called out Mario for wearing the Tanooki suit, which resembles a suit made of raccoon fur. PETA was seemingly quite serious about the whole thing, even releasing a flash game called Mario Kills Tanooki—but a few days later, following a lot of backlash, the organisation claimed it was all a joke.

Ars has asked Games Workshop for comment and will update this story if we get a response.