SEATTLE — It’s a Monday night at El Corazon here, and the Protomen are trying to figure out their set list. There are few recent standbys — they’ve been playing “Princes of the Universe” a lot on this tour — and the new song they debuted at PAX for an encore, but mostly they’ll stick with their signature work: a gritty post-apocalyptic rock opera about Mega Man.

By the time the Protomen take the stage, the audience is chanting and clapping, stomping in rhythm. Kilroy (the members of the Protomen perform under stage names, and although their actual identities are, at this point, something of an open secret we’ve agreed to stick with official titles for this article) comes on first, lit by a single spotlight. “Good evening, El Corazon,” he said, his voice tinny and warped behind a robot mask. “Good evening, Seattle, Washington.” The crowd roars. He banters about PAX for a moment, then pauses. His voice shifts to a dark growl.

“Seattle, Washington,” he said, “you know that we’re only here for one reason, and it ain’t face-melting rock’n’roll. Tonight, we come here to do battle. We’re here to fight tonight, Seattle, and we’re not gonna go at it alone. Seattle, Washington, will you fight with us this night?” More cheers, a sea of raised fists, yells resolving into a chant of Kilroy’s name. He continues: “Seattle, once again, will you fight with us?” The crowd explodes, again, louder.

Kilroy nods gravely, extends his arms like a preacher. “Your response is compliant,” he tells the crowd, robot-serious. And then: “We are your salvation. We are your hope. We are — the Protomen.”

And that’s when the face-melting rock’n’roll kicks in.

The Protomen are good. They’re really good. They’re cover-Queen-with-a-nine-person-band-and-get-away-with-it good.

When they’re not covering Queen — or Meat Loaf, or Bonnie Tyler, or Huey Lewis and the News — the Protomen are first and foremost a concept band. Two of their three albums are acts of an eponymous rock opera, a dark re-imagining of the early Mega Man games. That’s how they started playing in robot drag — the original gag was that they were robots built by Mega Man’s creator, Dr. Light, to tell his tragic story. Since then, the premise has slipped a little, but the silver facepaint stuck around, along with aviator shades and uniforms out of a post-apocalyptic Wild West. It’s all a little over-the-top—but that’s part of the point.

Offstage, they’re working on the final act, Act III, of their opera between tours and a handful of side projects — the live Queen cover album, the soundtrack to Shakespeare mash-up Terminator the Second, a collection of rock covers due out in 2014—and, announced yesterday, an original song for MM25: Mega Man Rocks, a 25th-anniversary anthology of songs about and from and inspired by the Mega Man videogames out in October. The Protomen debuted their song, “Built to Last,” live at PAX Prime; WIRED has an exclusive preview of the studio version, which you can hear below.

LISTEN: ‘Built to Last’ by The Protomen http://www.wired.com/images_blogs/underwire/2013/09/Built-To-Last.mp3

The Protomen came together for the first time in 2003, at Middle Tennessee State University, to record a last-minute assignment. “The first project wasn’t really intentionally about Mega Man,” keyboardist and songwriter Commander B. Hawkins — one of the handful of Protomen who’ve been there since the start — told WIRED. “It kind of just turned into it, kind of at the last second, ’cause the whole project was at the last second.” Although the song, “Due Vendetta,” was conceived, written, and recorded in less than a day it ended up picked as one of the class’s representatives for the end-of-the-semester program-wide listening night.

“And at that point we were like, ‘Well, we’ve got the people. We could go ahead and flesh it out and make a story out of it — make it into a big, tough-ass post-apocalyptic rock opera,'” Commander said. By the time they graduated, they had written and produced three more songs — “Hope Rides Alone,” “Unrest in the House of Light,” and “The Will of One,” which collectively form the backbone of the rock opera’s first act.

The Protomen finished the eponymous Act I album in 2005, and played a few live shows. They had talked about doing a second full-length record, but members were graduating and beginning to move away. The remaining band briefly flirted with the idea of a smaller project — a Dr. Light EP, which would eventually be folded into Act II. Then, a few months later, Nintendo Power called. They wanted to do a story about the band.

“All of a sudden more and more and more and more people got in touch and were, like, ‘I’ve got to have this.’ And we were like, ‘It kind of doesn’t really exist anymore,'” bassist Murphy Weller told WIRED. The Protomen‘s first album pressing had been 94 CDs, with screen-printed covers; the band had stapled the booklets by hand. “Suddenly, I was shipping orders to everywhere,” said Murphy. “That [Nintendo Power] article was what pushed it through, got us to the point of ‘Okay, let’s figure out how to do it.'” Act II: The Father of Death followed in 2009, with an expanded band roster and a more refined sound.

Ten years and two acts in, Protomen shows have an almost ritual feel: Kilroy’s invocation at the beginning, the costumes, moments when the helmets come on or off. Since the performance is ostensibly selections from a rock opera, the audience more often than not plays the chorus: a populace mourning Protoman’s fall (and later encouraging Mega Man to kill him), eager press corps during Dr. Wily’s triumphant villian anthem. They chant propaganda slogans, clap in time to a hero’s heartbeat, and call-and-respond with the performers. Some come in face paint, lugging helmets and home-made Mega Busters, dressed for the gritty streets of Dr. Wily’s techno-dystopia. Seeing the band live for the first time can feel like attending a political rally — or a very hard-rocking cult. With nine performers and a mountain of gear, they’ve become notorious for blowing fuses at smaller venues.

The Protomen play a lot of live shows — drummer Reanimator told WIRED that they’re on tour about five months out of every year. “Being on the road helps us in a number of ways,” Commander explained. “We’re sort of a hard band to explain, so it’s always good to introduce ourselves by dropping the hammer on a new crowd.”

At the same time, spending that much time on the road can be grueling, and it makes it difficult to write and record new material. “I think the worst part about being in the Protomen right now is that we’re at a stage where we could be in constant motion — we could constantly be touring — but we really need to stop,” said lead vocalist Raul Panther. “We can’t create an album while we’re on the road. Some bands can do that — write in the bus. But for us, it’s just — it’s too much with nine people in constant motion, to get anything of quality done while we’re on the road.”

The time commitments that come with touring as a Protoman also make it difficult for members to undertake other musical projects. Turbo Lover, who sings the part of Dr. Wily, joined the band in the lead-up to Act II. At the time, he was involved in several Nashville bands; now, he says, they’re mostly on back burners. “The Protomen started out as a side project, but it slowly developed so much momentum that it sort of ran over all the other projects. It doesn’t prohibit me from being creative, and playing solo shows and with other groups every once in a while, but after doing it professionally — I just don’t feel as excited about going out and doing a solo acoustic tour after being on tour with a rock opera,” he said.

Being back in Nashville comes with its own challenges. The Protomen are self-published and self-managed. “You have a lot of freedom when you’re doing everything yourself,” Commander said, “but you also have to do a lot of the work that would normally be handled by business types outside of the band. That sort of thing can slow down musical productivity.” And while the Protomen are big in videogame circles, most of the band members still work second jobs to make ends meet.

While the time they spend on tour and the size of the band are logistical challenges, they’re also among the Protomen’s greatest assets. “We were pretty loose at the beginning,” says Panther. “There were a lot of dirty rock’n’roll shows.” The Gambler, who’s been around since Act I, nods. “It’s a tighter, sleeker stage show now,” she says.

Their songwriting has tightened as well. As musicians, the members’ backgrounds range from traditional hard rock to classical composition, pop, folk-rock, and more; and all have found their way into the songwriting process, letting the Protomen achieve a stunning range of tone and style without sacrificing the band’s cohesive feel. “It’s easy for us to hone in on the musical scene—what we need the musical stage to be set as—and go from there,” Panther told WIRED. “But I like the fact that we don’t try to peg an entire album into one genre, one style of song.”

It’s that eclecticism that has fans waiting on the edge of their seats for Act III. Save for the one song the band debuted live in 2012, no one’s quite sure what to expect from the third and final chapter of the saga. In that respect, the Protomen are their own worst enemy: as they progress, each act they record becomes that much harder to follow.