The Walking Dead: How Daryl Dixon’s “Amped Up” Zombies Work

This article contains spoilers for The Walking Dead: Daryl Dixon finale.

When The Walking Dead‘s final season introduced zombie “variants” that could pull off physical maneuvers more sophisticated than your average walker, some fans were a little confused and perhaps even disappointed. One of those fans, it turns out, was The Walking Dead producer and resident zombie-maker-in-chief Greg Nicotero.

“The variants that were introduced in the last season of The Walking Dead didn’t make any sense,” Nicotero tells Den of Geek‘s Aaron Sagers. “Because it wasn’t earned. They were like ‘oh, if you go back to the first season, zombies use rocks and smash windows.’ It didn’t make any sense that after eleven seasons that we hadn’t seen any of that.”

As Nicotero mentions, The Walking Dead team did indeed try to explain away its walkers’ new skills by pointing to some examples of door-knob turning and apparent vestigial memories from season 1. Additionally, the lore-heavy post-credits scene in spinoff The Walking Dead: World Beyond suggested that French scientists had encountered some of these “variant cohort” zombies. Still, these new walkers seemed to violate the franchise’s very strict rules regarding the undead.

Now the latest Walking Dead spinoff Daryl Dixon has introduced more variants zombies of its own. As seen in the first episode of the season, some zombies are called “burners” or “boilers” and possess acidic qualities. In the final two episodes of the season, it’s revealed that zombies can be “amped up” into adrenaline monsters thanks to an injection of an unknown drug cocktail. How did Nicotero feel about this round of variants? Quite differently, actually.

“I think a lot of people would assume that I would have fought it because I’m a purist,” he says. “Zombies are zombies and they don’t really change. But I love the evolution of it.”

The new zombies of Daryl Dixon work because they’re consistent with the show’s lore in a way that the concept of natural occurring variants aren’t. Though Daryl Dixon showrunner David Zabel is new to the franchise, he wanted to make sure that the story operated within The Walking Dead‘s established rules, while also feeling fresh.

“The overall idea was ‘how do we come up with these obstacles that make the world scarier and harder without violating the rules of the universe?'” Zabel tells Den of Geek in a pre-finale interview. “It was determined that they can’t just be naturally occurring because that felt like a violation of the rules. So we came up with this idea that was partially inspired by evil scientific experimentation through the ages, including Nazi Germany.”

Crucially, Daryl Dixon‘s “boilers” and “ampers” (which is a term that Nicotero and Zabel both use to describe the super zombies that Daryl must fight in a thunder dome) are the product of human intervention and not merely any ill-defined mutation of a zombie virus. Human beings using the undead as a tool to harm other human beings is very much inline with The Walking Dead‘s themes over the years and doesn’t require as much suspension of disbelief to pull off. The fact that humans are involved also makes the process of creating super zombies satisfyingly imperfect.

“The idea is those zombies are only amped up for three or four minutes and then they sort of fizzle out. It doesn’t work with every single one,” Nictero says.

“They’re still trying. They haven’t succeeded fully to create this variant of walkers that is a weapon of destruction that can be used by [villain] Genet,” Zabel adds.

In addition to logically satisfying the terms set forward by The Walking Dead canon, burners and ampers gave Nicotero a fresh decaying canvas to play with. The gore expert points to the works of David Cronenberg (The Fly), Sam Raimi (The Evil Dead), and Dick Smith (Scanners) as inspirations for how to bring these unique rotters to life.

“[For the buners] we had the Scanners-like thick fluid, light colored veins. With the ampers, it’s more of a Sam Raimi Evil Dead tribute with the black veins like a demonic possession. The burners eyes are a weird bright blue almost like the base of a candle. The ampers eyes are black because that fluid affects everything inside.”

But what, exactly, is in that fluid that turns a mild-mannered zombie into a Captain America-esque super soldier?

“Maybe in season 2 we’ll find out. I think it’s French whisky,” Zabel says.

All six episodes of The Walking Dead: Daryl Dixon are available to stream on AMC+ now.